diff --git a/static/js/angular-animate.js b/static/js/angular-animate.js
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+/**
+ * @license AngularJS v1.5.8
+ * (c) 2010-2016 Google, Inc. http://angularjs.org
+ * License: MIT
+ */
+(function(window, angular) {'use strict';
+
+var ELEMENT_NODE = 1;
+var COMMENT_NODE = 8;
+
+var ADD_CLASS_SUFFIX = '-add';
+var REMOVE_CLASS_SUFFIX = '-remove';
+var EVENT_CLASS_PREFIX = 'ng-';
+var ACTIVE_CLASS_SUFFIX = '-active';
+var PREPARE_CLASS_SUFFIX = '-prepare';
+
+var NG_ANIMATE_CLASSNAME = 'ng-animate';
+var NG_ANIMATE_CHILDREN_DATA = '$$ngAnimateChildren';
+
+// Detect proper transitionend/animationend event names.
+var CSS_PREFIX = '', TRANSITION_PROP, TRANSITIONEND_EVENT, ANIMATION_PROP, ANIMATIONEND_EVENT;
+
+// If unprefixed events are not supported but webkit-prefixed are, use the latter.
+// Otherwise, just use W3C names, browsers not supporting them at all will just ignore them.
+// Note: Chrome implements `window.onwebkitanimationend` and doesn't implement `window.onanimationend`
+// but at the same time dispatches the `animationend` event and not `webkitAnimationEnd`.
+// Register both events in case `window.onanimationend` is not supported because of that,
+// do the same for `transitionend` as Safari is likely to exhibit similar behavior.
+// Also, the only modern browser that uses vendor prefixes for transitions/keyframes is webkit
+// therefore there is no reason to test anymore for other vendor prefixes:
+// http://caniuse.com/#search=transition
+if ((window.ontransitionend === void 0) && (window.onwebkittransitionend !== void 0)) {
+  CSS_PREFIX = '-webkit-';
+  TRANSITION_PROP = 'WebkitTransition';
+  TRANSITIONEND_EVENT = 'webkitTransitionEnd transitionend';
+} else {
+  TRANSITION_PROP = 'transition';
+  TRANSITIONEND_EVENT = 'transitionend';
+}
+
+if ((window.onanimationend === void 0) && (window.onwebkitanimationend !== void 0)) {
+  CSS_PREFIX = '-webkit-';
+  ANIMATION_PROP = 'WebkitAnimation';
+  ANIMATIONEND_EVENT = 'webkitAnimationEnd animationend';
+} else {
+  ANIMATION_PROP = 'animation';
+  ANIMATIONEND_EVENT = 'animationend';
+}
+
+var DURATION_KEY = 'Duration';
+var PROPERTY_KEY = 'Property';
+var DELAY_KEY = 'Delay';
+var TIMING_KEY = 'TimingFunction';
+var ANIMATION_ITERATION_COUNT_KEY = 'IterationCount';
+var ANIMATION_PLAYSTATE_KEY = 'PlayState';
+var SAFE_FAST_FORWARD_DURATION_VALUE = 9999;
+
+var ANIMATION_DELAY_PROP = ANIMATION_PROP + DELAY_KEY;
+var ANIMATION_DURATION_PROP = ANIMATION_PROP + DURATION_KEY;
+var TRANSITION_DELAY_PROP = TRANSITION_PROP + DELAY_KEY;
+var TRANSITION_DURATION_PROP = TRANSITION_PROP + DURATION_KEY;
+
+var ngMinErr = angular.$$minErr('ng');
+function assertArg(arg, name, reason) {
+  if (!arg) {
+    throw ngMinErr('areq', "Argument '{0}' is {1}", (name || '?'), (reason || "required"));
+  }
+  return arg;
+}
+
+function mergeClasses(a,b) {
+  if (!a && !b) return '';
+  if (!a) return b;
+  if (!b) return a;
+  if (isArray(a)) a = a.join(' ');
+  if (isArray(b)) b = b.join(' ');
+  return a + ' ' + b;
+}
+
+function packageStyles(options) {
+  var styles = {};
+  if (options && (options.to || options.from)) {
+    styles.to = options.to;
+    styles.from = options.from;
+  }
+  return styles;
+}
+
+function pendClasses(classes, fix, isPrefix) {
+  var className = '';
+  classes = isArray(classes)
+      ? classes
+      : classes && isString(classes) && classes.length
+          ? classes.split(/\s+/)
+          : [];
+  forEach(classes, function(klass, i) {
+    if (klass && klass.length > 0) {
+      className += (i > 0) ? ' ' : '';
+      className += isPrefix ? fix + klass
+                            : klass + fix;
+    }
+  });
+  return className;
+}
+
+function removeFromArray(arr, val) {
+  var index = arr.indexOf(val);
+  if (val >= 0) {
+    arr.splice(index, 1);
+  }
+}
+
+function stripCommentsFromElement(element) {
+  if (element instanceof jqLite) {
+    switch (element.length) {
+      case 0:
+        return element;
+
+      case 1:
+        // there is no point of stripping anything if the element
+        // is the only element within the jqLite wrapper.
+        // (it's important that we retain the element instance.)
+        if (element[0].nodeType === ELEMENT_NODE) {
+          return element;
+        }
+        break;
+
+      default:
+        return jqLite(extractElementNode(element));
+    }
+  }
+
+  if (element.nodeType === ELEMENT_NODE) {
+    return jqLite(element);
+  }
+}
+
+function extractElementNode(element) {
+  if (!element[0]) return element;
+  for (var i = 0; i < element.length; i++) {
+    var elm = element[i];
+    if (elm.nodeType == ELEMENT_NODE) {
+      return elm;
+    }
+  }
+}
+
+function $$addClass($$jqLite, element, className) {
+  forEach(element, function(elm) {
+    $$jqLite.addClass(elm, className);
+  });
+}
+
+function $$removeClass($$jqLite, element, className) {
+  forEach(element, function(elm) {
+    $$jqLite.removeClass(elm, className);
+  });
+}
+
+function applyAnimationClassesFactory($$jqLite) {
+  return function(element, options) {
+    if (options.addClass) {
+      $$addClass($$jqLite, element, options.addClass);
+      options.addClass = null;
+    }
+    if (options.removeClass) {
+      $$removeClass($$jqLite, element, options.removeClass);
+      options.removeClass = null;
+    }
+  };
+}
+
+function prepareAnimationOptions(options) {
+  options = options || {};
+  if (!options.$$prepared) {
+    var domOperation = options.domOperation || noop;
+    options.domOperation = function() {
+      options.$$domOperationFired = true;
+      domOperation();
+      domOperation = noop;
+    };
+    options.$$prepared = true;
+  }
+  return options;
+}
+
+function applyAnimationStyles(element, options) {
+  applyAnimationFromStyles(element, options);
+  applyAnimationToStyles(element, options);
+}
+
+function applyAnimationFromStyles(element, options) {
+  if (options.from) {
+    element.css(options.from);
+    options.from = null;
+  }
+}
+
+function applyAnimationToStyles(element, options) {
+  if (options.to) {
+    element.css(options.to);
+    options.to = null;
+  }
+}
+
+function mergeAnimationDetails(element, oldAnimation, newAnimation) {
+  var target = oldAnimation.options || {};
+  var newOptions = newAnimation.options || {};
+
+  var toAdd = (target.addClass || '') + ' ' + (newOptions.addClass || '');
+  var toRemove = (target.removeClass || '') + ' ' + (newOptions.removeClass || '');
+  var classes = resolveElementClasses(element.attr('class'), toAdd, toRemove);
+
+  if (newOptions.preparationClasses) {
+    target.preparationClasses = concatWithSpace(newOptions.preparationClasses, target.preparationClasses);
+    delete newOptions.preparationClasses;
+  }
+
+  // noop is basically when there is no callback; otherwise something has been set
+  var realDomOperation = target.domOperation !== noop ? target.domOperation : null;
+
+  extend(target, newOptions);
+
+  // TODO(matsko or sreeramu): proper fix is to maintain all animation callback in array and call at last,but now only leave has the callback so no issue with this.
+  if (realDomOperation) {
+    target.domOperation = realDomOperation;
+  }
+
+  if (classes.addClass) {
+    target.addClass = classes.addClass;
+  } else {
+    target.addClass = null;
+  }
+
+  if (classes.removeClass) {
+    target.removeClass = classes.removeClass;
+  } else {
+    target.removeClass = null;
+  }
+
+  oldAnimation.addClass = target.addClass;
+  oldAnimation.removeClass = target.removeClass;
+
+  return target;
+}
+
+function resolveElementClasses(existing, toAdd, toRemove) {
+  var ADD_CLASS = 1;
+  var REMOVE_CLASS = -1;
+
+  var flags = {};
+  existing = splitClassesToLookup(existing);
+
+  toAdd = splitClassesToLookup(toAdd);
+  forEach(toAdd, function(value, key) {
+    flags[key] = ADD_CLASS;
+  });
+
+  toRemove = splitClassesToLookup(toRemove);
+  forEach(toRemove, function(value, key) {
+    flags[key] = flags[key] === ADD_CLASS ? null : REMOVE_CLASS;
+  });
+
+  var classes = {
+    addClass: '',
+    removeClass: ''
+  };
+
+  forEach(flags, function(val, klass) {
+    var prop, allow;
+    if (val === ADD_CLASS) {
+      prop = 'addClass';
+      allow = !existing[klass] || existing[klass + REMOVE_CLASS_SUFFIX];
+    } else if (val === REMOVE_CLASS) {
+      prop = 'removeClass';
+      allow = existing[klass] || existing[klass + ADD_CLASS_SUFFIX];
+    }
+    if (allow) {
+      if (classes[prop].length) {
+        classes[prop] += ' ';
+      }
+      classes[prop] += klass;
+    }
+  });
+
+  function splitClassesToLookup(classes) {
+    if (isString(classes)) {
+      classes = classes.split(' ');
+    }
+
+    var obj = {};
+    forEach(classes, function(klass) {
+      // sometimes the split leaves empty string values
+      // incase extra spaces were applied to the options
+      if (klass.length) {
+        obj[klass] = true;
+      }
+    });
+    return obj;
+  }
+
+  return classes;
+}
+
+function getDomNode(element) {
+  return (element instanceof jqLite) ? element[0] : element;
+}
+
+function applyGeneratedPreparationClasses(element, event, options) {
+  var classes = '';
+  if (event) {
+    classes = pendClasses(event, EVENT_CLASS_PREFIX, true);
+  }
+  if (options.addClass) {
+    classes = concatWithSpace(classes, pendClasses(options.addClass, ADD_CLASS_SUFFIX));
+  }
+  if (options.removeClass) {
+    classes = concatWithSpace(classes, pendClasses(options.removeClass, REMOVE_CLASS_SUFFIX));
+  }
+  if (classes.length) {
+    options.preparationClasses = classes;
+    element.addClass(classes);
+  }
+}
+
+function clearGeneratedClasses(element, options) {
+  if (options.preparationClasses) {
+    element.removeClass(options.preparationClasses);
+    options.preparationClasses = null;
+  }
+  if (options.activeClasses) {
+    element.removeClass(options.activeClasses);
+    options.activeClasses = null;
+  }
+}
+
+function blockTransitions(node, duration) {
+  // we use a negative delay value since it performs blocking
+  // yet it doesn't kill any existing transitions running on the
+  // same element which makes this safe for class-based animations
+  var value = duration ? '-' + duration + 's' : '';
+  applyInlineStyle(node, [TRANSITION_DELAY_PROP, value]);
+  return [TRANSITION_DELAY_PROP, value];
+}
+
+function blockKeyframeAnimations(node, applyBlock) {
+  var value = applyBlock ? 'paused' : '';
+  var key = ANIMATION_PROP + ANIMATION_PLAYSTATE_KEY;
+  applyInlineStyle(node, [key, value]);
+  return [key, value];
+}
+
+function applyInlineStyle(node, styleTuple) {
+  var prop = styleTuple[0];
+  var value = styleTuple[1];
+  node.style[prop] = value;
+}
+
+function concatWithSpace(a,b) {
+  if (!a) return b;
+  if (!b) return a;
+  return a + ' ' + b;
+}
+
+var $$rAFSchedulerFactory = ['$$rAF', function($$rAF) {
+  var queue, cancelFn;
+
+  function scheduler(tasks) {
+    // we make a copy since RAFScheduler mutates the state
+    // of the passed in array variable and this would be difficult
+    // to track down on the outside code
+    queue = queue.concat(tasks);
+    nextTick();
+  }
+
+  queue = scheduler.queue = [];
+
+  /* waitUntilQuiet does two things:
+   * 1. It will run the FINAL `fn` value only when an uncanceled RAF has passed through
+   * 2. It will delay the next wave of tasks from running until the quiet `fn` has run.
+   *
+   * The motivation here is that animation code can request more time from the scheduler
+   * before the next wave runs. This allows for certain DOM properties such as classes to
+   * be resolved in time for the next animation to run.
+   */
+  scheduler.waitUntilQuiet = function(fn) {
+    if (cancelFn) cancelFn();
+
+    cancelFn = $$rAF(function() {
+      cancelFn = null;
+      fn();
+      nextTick();
+    });
+  };
+
+  return scheduler;
+
+  function nextTick() {
+    if (!queue.length) return;
+
+    var items = queue.shift();
+    for (var i = 0; i < items.length; i++) {
+      items[i]();
+    }
+
+    if (!cancelFn) {
+      $$rAF(function() {
+        if (!cancelFn) nextTick();
+      });
+    }
+  }
+}];
+
+/**
+ * @ngdoc directive
+ * @name ngAnimateChildren
+ * @restrict AE
+ * @element ANY
+ *
+ * @description
+ *
+ * ngAnimateChildren allows you to specify that children of this element should animate even if any
+ * of the children's parents are currently animating. By default, when an element has an active `enter`, `leave`, or `move`
+ * (structural) animation, child elements that also have an active structural animation are not animated.
+ *
+ * Note that even if `ngAnimteChildren` is set, no child animations will run when the parent element is removed from the DOM (`leave` animation).
+ *
+ *
+ * @param {string} ngAnimateChildren If the value is empty, `true` or `on`,
+ *     then child animations are allowed. If the value is `false`, child animations are not allowed.
+ *
+ * @example
+ * <example module="ngAnimateChildren" name="ngAnimateChildren" deps="angular-animate.js" animations="true">
+     <file name="index.html">
+       <div ng-controller="mainController as main">
+         <label>Show container? <input type="checkbox" ng-model="main.enterElement" /></label>
+         <label>Animate children? <input type="checkbox" ng-model="main.animateChildren" /></label>
+         <hr>
+         <div ng-animate-children="{{main.animateChildren}}">
+           <div ng-if="main.enterElement" class="container">
+             List of items:
+             <div ng-repeat="item in [0, 1, 2, 3]" class="item">Item {{item}}</div>
+           </div>
+         </div>
+       </div>
+     </file>
+     <file name="animations.css">
+
+      .container.ng-enter,
+      .container.ng-leave {
+        transition: all ease 1.5s;
+      }
+
+      .container.ng-enter,
+      .container.ng-leave-active {
+        opacity: 0;
+      }
+
+      .container.ng-leave,
+      .container.ng-enter-active {
+        opacity: 1;
+      }
+
+      .item {
+        background: firebrick;
+        color: #FFF;
+        margin-bottom: 10px;
+      }
+
+      .item.ng-enter,
+      .item.ng-leave {
+        transition: transform 1.5s ease;
+      }
+
+      .item.ng-enter {
+        transform: translateX(50px);
+      }
+
+      .item.ng-enter-active {
+        transform: translateX(0);
+      }
+    </file>
+    <file name="script.js">
+      angular.module('ngAnimateChildren', ['ngAnimate'])
+        .controller('mainController', function() {
+          this.animateChildren = false;
+          this.enterElement = false;
+        });
+    </file>
+  </example>
+ */
+var $$AnimateChildrenDirective = ['$interpolate', function($interpolate) {
+  return {
+    link: function(scope, element, attrs) {
+      var val = attrs.ngAnimateChildren;
+      if (isString(val) && val.length === 0) { //empty attribute
+        element.data(NG_ANIMATE_CHILDREN_DATA, true);
+      } else {
+        // Interpolate and set the value, so that it is available to
+        // animations that run right after compilation
+        setData($interpolate(val)(scope));
+        attrs.$observe('ngAnimateChildren', setData);
+      }
+
+      function setData(value) {
+        value = value === 'on' || value === 'true';
+        element.data(NG_ANIMATE_CHILDREN_DATA, value);
+      }
+    }
+  };
+}];
+
+var ANIMATE_TIMER_KEY = '$$animateCss';
+
+/**
+ * @ngdoc service
+ * @name $animateCss
+ * @kind object
+ *
+ * @description
+ * The `$animateCss` service is a useful utility to trigger customized CSS-based transitions/keyframes
+ * from a JavaScript-based animation or directly from a directive. The purpose of `$animateCss` is NOT
+ * to side-step how `$animate` and ngAnimate work, but the goal is to allow pre-existing animations or
+ * directives to create more complex animations that can be purely driven using CSS code.
+ *
+ * Note that only browsers that support CSS transitions and/or keyframe animations are capable of
+ * rendering animations triggered via `$animateCss` (bad news for IE9 and lower).
+ *
+ * ## Usage
+ * Once again, `$animateCss` is designed to be used inside of a registered JavaScript animation that
+ * is powered by ngAnimate. It is possible to use `$animateCss` directly inside of a directive, however,
+ * any automatic control over cancelling animations and/or preventing animations from being run on
+ * child elements will not be handled by Angular. For this to work as expected, please use `$animate` to
+ * trigger the animation and then setup a JavaScript animation that injects `$animateCss` to trigger
+ * the CSS animation.
+ *
+ * The example below shows how we can create a folding animation on an element using `ng-if`:
+ *
+ * ```html
+ * <!-- notice the `fold-animation` CSS class -->
+ * <div ng-if="onOff" class="fold-animation">
+ *   This element will go BOOM
+ * </div>
+ * <button ng-click="onOff=true">Fold In</button>
+ * ```
+ *
+ * Now we create the **JavaScript animation** that will trigger the CSS transition:
+ *
+ * ```js
+ * ngModule.animation('.fold-animation', ['$animateCss', function($animateCss) {
+ *   return {
+ *     enter: function(element, doneFn) {
+ *       var height = element[0].offsetHeight;
+ *       return $animateCss(element, {
+ *         from: { height:'0px' },
+ *         to: { height:height + 'px' },
+ *         duration: 1 // one second
+ *       });
+ *     }
+ *   }
+ * }]);
+ * ```
+ *
+ * ## More Advanced Uses
+ *
+ * `$animateCss` is the underlying code that ngAnimate uses to power **CSS-based animations** behind the scenes. Therefore CSS hooks
+ * like `.ng-EVENT`, `.ng-EVENT-active`, `.ng-EVENT-stagger` are all features that can be triggered using `$animateCss` via JavaScript code.
+ *
+ * This also means that just about any combination of adding classes, removing classes, setting styles, dynamically setting a keyframe animation,
+ * applying a hardcoded duration or delay value, changing the animation easing or applying a stagger animation are all options that work with
+ * `$animateCss`. The service itself is smart enough to figure out the combination of options and examine the element styling properties in order
+ * to provide a working animation that will run in CSS.
+ *
+ * The example below showcases a more advanced version of the `.fold-animation` from the example above:
+ *
+ * ```js
+ * ngModule.animation('.fold-animation', ['$animateCss', function($animateCss) {
+ *   return {
+ *     enter: function(element, doneFn) {
+ *       var height = element[0].offsetHeight;
+ *       return $animateCss(element, {
+ *         addClass: 'red large-text pulse-twice',
+ *         easing: 'ease-out',
+ *         from: { height:'0px' },
+ *         to: { height:height + 'px' },
+ *         duration: 1 // one second
+ *       });
+ *     }
+ *   }
+ * }]);
+ * ```
+ *
+ * Since we're adding/removing CSS classes then the CSS transition will also pick those up:
+ *
+ * ```css
+ * /&#42; since a hardcoded duration value of 1 was provided in the JavaScript animation code,
+ * the CSS classes below will be transitioned despite them being defined as regular CSS classes &#42;/
+ * .red { background:red; }
+ * .large-text { font-size:20px; }
+ *
+ * /&#42; we can also use a keyframe animation and $animateCss will make it work alongside the transition &#42;/
+ * .pulse-twice {
+ *   animation: 0.5s pulse linear 2;
+ *   -webkit-animation: 0.5s pulse linear 2;
+ * }
+ *
+ * @keyframes pulse {
+ *   from { transform: scale(0.5); }
+ *   to { transform: scale(1.5); }
+ * }
+ *
+ * @-webkit-keyframes pulse {
+ *   from { -webkit-transform: scale(0.5); }
+ *   to { -webkit-transform: scale(1.5); }
+ * }
+ * ```
+ *
+ * Given this complex combination of CSS classes, styles and options, `$animateCss` will figure everything out and make the animation happen.
+ *
+ * ## How the Options are handled
+ *
+ * `$animateCss` is very versatile and intelligent when it comes to figuring out what configurations to apply to the element to ensure the animation
+ * works with the options provided. Say for example we were adding a class that contained a keyframe value and we wanted to also animate some inline
+ * styles using the `from` and `to` properties.
+ *
+ * ```js
+ * var animator = $animateCss(element, {
+ *   from: { background:'red' },
+ *   to: { background:'blue' }
+ * });
+ * animator.start();
+ * ```
+ *
+ * ```css
+ * .rotating-animation {
+ *   animation:0.5s rotate linear;
+ *   -webkit-animation:0.5s rotate linear;
+ * }
+ *
+ * @keyframes rotate {
+ *   from { transform: rotate(0deg); }
+ *   to { transform: rotate(360deg); }
+ * }
+ *
+ * @-webkit-keyframes rotate {
+ *   from { -webkit-transform: rotate(0deg); }
+ *   to { -webkit-transform: rotate(360deg); }
+ * }
+ * ```
+ *
+ * The missing pieces here are that we do not have a transition set (within the CSS code nor within the `$animateCss` options) and the duration of the animation is
+ * going to be detected from what the keyframe styles on the CSS class are. In this event, `$animateCss` will automatically create an inline transition
+ * style matching the duration detected from the keyframe style (which is present in the CSS class that is being added) and then prepare both the transition
+ * and keyframe animations to run in parallel on the element. Then when the animation is underway the provided `from` and `to` CSS styles will be applied
+ * and spread across the transition and keyframe animation.
+ *
+ * ## What is returned
+ *
+ * `$animateCss` works in two stages: a preparation phase and an animation phase. Therefore when `$animateCss` is first called it will NOT actually
+ * start the animation. All that is going on here is that the element is being prepared for the animation (which means that the generated CSS classes are
+ * added and removed on the element). Once `$animateCss` is called it will return an object with the following properties:
+ *
+ * ```js
+ * var animator = $animateCss(element, { ... });
+ * ```
+ *
+ * Now what do the contents of our `animator` variable look like:
+ *
+ * ```js
+ * {
+ *   // starts the animation
+ *   start: Function,
+ *
+ *   // ends (aborts) the animation
+ *   end: Function
+ * }
+ * ```
+ *
+ * To actually start the animation we need to run `animation.start()` which will then return a promise that we can hook into to detect when the animation ends.
+ * If we choose not to run the animation then we MUST run `animation.end()` to perform a cleanup on the element (since some CSS classes and styles may have been
+ * applied to the element during the preparation phase). Note that all other properties such as duration, delay, transitions and keyframes are just properties
+ * and that changing them will not reconfigure the parameters of the animation.
+ *
+ * ### runner.done() vs runner.then()
+ * It is documented that `animation.start()` will return a promise object and this is true, however, there is also an additional method available on the
+ * runner called `.done(callbackFn)`. The done method works the same as `.finally(callbackFn)`, however, it does **not trigger a digest to occur**.
+ * Therefore, for performance reasons, it's always best to use `runner.done(callback)` instead of `runner.then()`, `runner.catch()` or `runner.finally()`
+ * unless you really need a digest to kick off afterwards.
+ *
+ * Keep in mind that, to make this easier, ngAnimate has tweaked the JS animations API to recognize when a runner instance is returned from $animateCss
+ * (so there is no need to call `runner.done(doneFn)` inside of your JavaScript animation code).
+ * Check the {@link ngAnimate.$animateCss#usage animation code above} to see how this works.
+ *
+ * @param {DOMElement} element the element that will be animated
+ * @param {object} options the animation-related options that will be applied during the animation
+ *
+ * * `event` - The DOM event (e.g. enter, leave, move). When used, a generated CSS class of `ng-EVENT` and `ng-EVENT-active` will be applied
+ * to the element during the animation. Multiple events can be provided when spaces are used as a separator. (Note that this will not perform any DOM operation.)
+ * * `structural` - Indicates that the `ng-` prefix will be added to the event class. Setting to `false` or omitting will turn `ng-EVENT` and
+ * `ng-EVENT-active` in `EVENT` and `EVENT-active`. Unused if `event` is omitted.
+ * * `easing` - The CSS easing value that will be applied to the transition or keyframe animation (or both).
+ * * `transitionStyle` - The raw CSS transition style that will be used (e.g. `1s linear all`).
+ * * `keyframeStyle` - The raw CSS keyframe animation style that will be used (e.g. `1s my_animation linear`).
+ * * `from` - The starting CSS styles (a key/value object) that will be applied at the start of the animation.
+ * * `to` - The ending CSS styles (a key/value object) that will be applied across the animation via a CSS transition.
+ * * `addClass` - A space separated list of CSS classes that will be added to the element and spread across the animation.
+ * * `removeClass` - A space separated list of CSS classes that will be removed from the element and spread across the animation.
+ * * `duration` - A number value representing the total duration of the transition and/or keyframe (note that a value of 1 is 1000ms). If a value of `0`
+ * is provided then the animation will be skipped entirely.
+ * * `delay` - A number value representing the total delay of the transition and/or keyframe (note that a value of 1 is 1000ms). If a value of `true` is
+ * used then whatever delay value is detected from the CSS classes will be mirrored on the elements styles (e.g. by setting delay true then the style value
+ * of the element will be `transition-delay: DETECTED_VALUE`). Using `true` is useful when you want the CSS classes and inline styles to all share the same
+ * CSS delay value.
+ * * `stagger` - A numeric time value representing the delay between successively animated elements
+ * ({@link ngAnimate#css-staggering-animations Click here to learn how CSS-based staggering works in ngAnimate.})
+ * * `staggerIndex` - The numeric index representing the stagger item (e.g. a value of 5 is equal to the sixth item in the stagger; therefore when a
+ *   `stagger` option value of `0.1` is used then there will be a stagger delay of `600ms`)
+ * * `applyClassesEarly` - Whether or not the classes being added or removed will be used when detecting the animation. This is set by `$animate` when enter/leave/move animations are fired to ensure that the CSS classes are resolved in time. (Note that this will prevent any transitions from occurring on the classes being added and removed.)
+ * * `cleanupStyles` - Whether or not the provided `from` and `to` styles will be removed once
+ *    the animation is closed. This is useful for when the styles are used purely for the sake of
+ *    the animation and do not have a lasting visual effect on the element (e.g. a collapse and open animation).
+ *    By default this value is set to `false`.
+ *
+ * @return {object} an object with start and end methods and details about the animation.
+ *
+ * * `start` - The method to start the animation. This will return a `Promise` when called.
+ * * `end` - This method will cancel the animation and remove all applied CSS classes and styles.
+ */
+var ONE_SECOND = 1000;
+var BASE_TEN = 10;
+
+var ELAPSED_TIME_MAX_DECIMAL_PLACES = 3;
+var CLOSING_TIME_BUFFER = 1.5;
+
+var DETECT_CSS_PROPERTIES = {
+  transitionDuration:      TRANSITION_DURATION_PROP,
+  transitionDelay:         TRANSITION_DELAY_PROP,
+  transitionProperty:      TRANSITION_PROP + PROPERTY_KEY,
+  animationDuration:       ANIMATION_DURATION_PROP,
+  animationDelay:          ANIMATION_DELAY_PROP,
+  animationIterationCount: ANIMATION_PROP + ANIMATION_ITERATION_COUNT_KEY
+};
+
+var DETECT_STAGGER_CSS_PROPERTIES = {
+  transitionDuration:      TRANSITION_DURATION_PROP,
+  transitionDelay:         TRANSITION_DELAY_PROP,
+  animationDuration:       ANIMATION_DURATION_PROP,
+  animationDelay:          ANIMATION_DELAY_PROP
+};
+
+function getCssKeyframeDurationStyle(duration) {
+  return [ANIMATION_DURATION_PROP, duration + 's'];
+}
+
+function getCssDelayStyle(delay, isKeyframeAnimation) {
+  var prop = isKeyframeAnimation ? ANIMATION_DELAY_PROP : TRANSITION_DELAY_PROP;
+  return [prop, delay + 's'];
+}
+
+function computeCssStyles($window, element, properties) {
+  var styles = Object.create(null);
+  var detectedStyles = $window.getComputedStyle(element) || {};
+  forEach(properties, function(formalStyleName, actualStyleName) {
+    var val = detectedStyles[formalStyleName];
+    if (val) {
+      var c = val.charAt(0);
+
+      // only numerical-based values have a negative sign or digit as the first value
+      if (c === '-' || c === '+' || c >= 0) {
+        val = parseMaxTime(val);
+      }
+
+      // by setting this to null in the event that the delay is not set or is set directly as 0
+      // then we can still allow for negative values to be used later on and not mistake this
+      // value for being greater than any other negative value.
+      if (val === 0) {
+        val = null;
+      }
+      styles[actualStyleName] = val;
+    }
+  });
+
+  return styles;
+}
+
+function parseMaxTime(str) {
+  var maxValue = 0;
+  var values = str.split(/\s*,\s*/);
+  forEach(values, function(value) {
+    // it's always safe to consider only second values and omit `ms` values since
+    // getComputedStyle will always handle the conversion for us
+    if (value.charAt(value.length - 1) == 's') {
+      value = value.substring(0, value.length - 1);
+    }
+    value = parseFloat(value) || 0;
+    maxValue = maxValue ? Math.max(value, maxValue) : value;
+  });
+  return maxValue;
+}
+
+function truthyTimingValue(val) {
+  return val === 0 || val != null;
+}
+
+function getCssTransitionDurationStyle(duration, applyOnlyDuration) {
+  var style = TRANSITION_PROP;
+  var value = duration + 's';
+  if (applyOnlyDuration) {
+    style += DURATION_KEY;
+  } else {
+    value += ' linear all';
+  }
+  return [style, value];
+}
+
+function createLocalCacheLookup() {
+  var cache = Object.create(null);
+  return {
+    flush: function() {
+      cache = Object.create(null);
+    },
+
+    count: function(key) {
+      var entry = cache[key];
+      return entry ? entry.total : 0;
+    },
+
+    get: function(key) {
+      var entry = cache[key];
+      return entry && entry.value;
+    },
+
+    put: function(key, value) {
+      if (!cache[key]) {
+        cache[key] = { total: 1, value: value };
+      } else {
+        cache[key].total++;
+      }
+    }
+  };
+}
+
+// we do not reassign an already present style value since
+// if we detect the style property value again we may be
+// detecting styles that were added via the `from` styles.
+// We make use of `isDefined` here since an empty string
+// or null value (which is what getPropertyValue will return
+// for a non-existing style) will still be marked as a valid
+// value for the style (a falsy value implies that the style
+// is to be removed at the end of the animation). If we had a simple
+// "OR" statement then it would not be enough to catch that.
+function registerRestorableStyles(backup, node, properties) {
+  forEach(properties, function(prop) {
+    backup[prop] = isDefined(backup[prop])
+        ? backup[prop]
+        : node.style.getPropertyValue(prop);
+  });
+}
+
+var $AnimateCssProvider = ['$animateProvider', function($animateProvider) {
+  var gcsLookup = createLocalCacheLookup();
+  var gcsStaggerLookup = createLocalCacheLookup();
+
+  this.$get = ['$window', '$$jqLite', '$$AnimateRunner', '$timeout',
+               '$$forceReflow', '$sniffer', '$$rAFScheduler', '$$animateQueue',
+       function($window,   $$jqLite,   $$AnimateRunner,   $timeout,
+                $$forceReflow,   $sniffer,   $$rAFScheduler, $$animateQueue) {
+
+    var applyAnimationClasses = applyAnimationClassesFactory($$jqLite);
+
+    var parentCounter = 0;
+    function gcsHashFn(node, extraClasses) {
+      var KEY = "$$ngAnimateParentKey";
+      var parentNode = node.parentNode;
+      var parentID = parentNode[KEY] || (parentNode[KEY] = ++parentCounter);
+      return parentID + '-' + node.getAttribute('class') + '-' + extraClasses;
+    }
+
+    function computeCachedCssStyles(node, className, cacheKey, properties) {
+      var timings = gcsLookup.get(cacheKey);
+
+      if (!timings) {
+        timings = computeCssStyles($window, node, properties);
+        if (timings.animationIterationCount === 'infinite') {
+          timings.animationIterationCount = 1;
+        }
+      }
+
+      // we keep putting this in multiple times even though the value and the cacheKey are the same
+      // because we're keeping an internal tally of how many duplicate animations are detected.
+      gcsLookup.put(cacheKey, timings);
+      return timings;
+    }
+
+    function computeCachedCssStaggerStyles(node, className, cacheKey, properties) {
+      var stagger;
+
+      // if we have one or more existing matches of matching elements
+      // containing the same parent + CSS styles (which is how cacheKey works)
+      // then staggering is possible
+      if (gcsLookup.count(cacheKey) > 0) {
+        stagger = gcsStaggerLookup.get(cacheKey);
+
+        if (!stagger) {
+          var staggerClassName = pendClasses(className, '-stagger');
+
+          $$jqLite.addClass(node, staggerClassName);
+
+          stagger = computeCssStyles($window, node, properties);
+
+          // force the conversion of a null value to zero incase not set
+          stagger.animationDuration = Math.max(stagger.animationDuration, 0);
+          stagger.transitionDuration = Math.max(stagger.transitionDuration, 0);
+
+          $$jqLite.removeClass(node, staggerClassName);
+
+          gcsStaggerLookup.put(cacheKey, stagger);
+        }
+      }
+
+      return stagger || {};
+    }
+
+    var cancelLastRAFRequest;
+    var rafWaitQueue = [];
+    function waitUntilQuiet(callback) {
+      rafWaitQueue.push(callback);
+      $$rAFScheduler.waitUntilQuiet(function() {
+        gcsLookup.flush();
+        gcsStaggerLookup.flush();
+
+        // DO NOT REMOVE THIS LINE OR REFACTOR OUT THE `pageWidth` variable.
+        // PLEASE EXAMINE THE `$$forceReflow` service to understand why.
+        var pageWidth = $$forceReflow();
+
+        // we use a for loop to ensure that if the queue is changed
+        // during this looping then it will consider new requests
+        for (var i = 0; i < rafWaitQueue.length; i++) {
+          rafWaitQueue[i](pageWidth);
+        }
+        rafWaitQueue.length = 0;
+      });
+    }
+
+    function computeTimings(node, className, cacheKey) {
+      var timings = computeCachedCssStyles(node, className, cacheKey, DETECT_CSS_PROPERTIES);
+      var aD = timings.animationDelay;
+      var tD = timings.transitionDelay;
+      timings.maxDelay = aD && tD
+          ? Math.max(aD, tD)
+          : (aD || tD);
+      timings.maxDuration = Math.max(
+          timings.animationDuration * timings.animationIterationCount,
+          timings.transitionDuration);
+
+      return timings;
+    }
+
+    return function init(element, initialOptions) {
+      // all of the animation functions should create
+      // a copy of the options data, however, if a
+      // parent service has already created a copy then
+      // we should stick to using that
+      var options = initialOptions || {};
+      if (!options.$$prepared) {
+        options = prepareAnimationOptions(copy(options));
+      }
+
+      var restoreStyles = {};
+      var node = getDomNode(element);
+      if (!node
+          || !node.parentNode
+          || !$$animateQueue.enabled()) {
+        return closeAndReturnNoopAnimator();
+      }
+
+      var temporaryStyles = [];
+      var classes = element.attr('class');
+      var styles = packageStyles(options);
+      var animationClosed;
+      var animationPaused;
+      var animationCompleted;
+      var runner;
+      var runnerHost;
+      var maxDelay;
+      var maxDelayTime;
+      var maxDuration;
+      var maxDurationTime;
+      var startTime;
+      var events = [];
+
+      if (options.duration === 0 || (!$sniffer.animations && !$sniffer.transitions)) {
+        return closeAndReturnNoopAnimator();
+      }
+
+      var method = options.event && isArray(options.event)
+            ? options.event.join(' ')
+            : options.event;
+
+      var isStructural = method && options.structural;
+      var structuralClassName = '';
+      var addRemoveClassName = '';
+
+      if (isStructural) {
+        structuralClassName = pendClasses(method, EVENT_CLASS_PREFIX, true);
+      } else if (method) {
+        structuralClassName = method;
+      }
+
+      if (options.addClass) {
+        addRemoveClassName += pendClasses(options.addClass, ADD_CLASS_SUFFIX);
+      }
+
+      if (options.removeClass) {
+        if (addRemoveClassName.length) {
+          addRemoveClassName += ' ';
+        }
+        addRemoveClassName += pendClasses(options.removeClass, REMOVE_CLASS_SUFFIX);
+      }
+
+      // there may be a situation where a structural animation is combined together
+      // with CSS classes that need to resolve before the animation is computed.
+      // However this means that there is no explicit CSS code to block the animation
+      // from happening (by setting 0s none in the class name). If this is the case
+      // we need to apply the classes before the first rAF so we know to continue if
+      // there actually is a detected transition or keyframe animation
+      if (options.applyClassesEarly && addRemoveClassName.length) {
+        applyAnimationClasses(element, options);
+      }
+
+      var preparationClasses = [structuralClassName, addRemoveClassName].join(' ').trim();
+      var fullClassName = classes + ' ' + preparationClasses;
+      var activeClasses = pendClasses(preparationClasses, ACTIVE_CLASS_SUFFIX);
+      var hasToStyles = styles.to && Object.keys(styles.to).length > 0;
+      var containsKeyframeAnimation = (options.keyframeStyle || '').length > 0;
+
+      // there is no way we can trigger an animation if no styles and
+      // no classes are being applied which would then trigger a transition,
+      // unless there a is raw keyframe value that is applied to the element.
+      if (!containsKeyframeAnimation
+           && !hasToStyles
+           && !preparationClasses) {
+        return closeAndReturnNoopAnimator();
+      }
+
+      var cacheKey, stagger;
+      if (options.stagger > 0) {
+        var staggerVal = parseFloat(options.stagger);
+        stagger = {
+          transitionDelay: staggerVal,
+          animationDelay: staggerVal,
+          transitionDuration: 0,
+          animationDuration: 0
+        };
+      } else {
+        cacheKey = gcsHashFn(node, fullClassName);
+        stagger = computeCachedCssStaggerStyles(node, preparationClasses, cacheKey, DETECT_STAGGER_CSS_PROPERTIES);
+      }
+
+      if (!options.$$skipPreparationClasses) {
+        $$jqLite.addClass(element, preparationClasses);
+      }
+
+      var applyOnlyDuration;
+
+      if (options.transitionStyle) {
+        var transitionStyle = [TRANSITION_PROP, options.transitionStyle];
+        applyInlineStyle(node, transitionStyle);
+        temporaryStyles.push(transitionStyle);
+      }
+
+      if (options.duration >= 0) {
+        applyOnlyDuration = node.style[TRANSITION_PROP].length > 0;
+        var durationStyle = getCssTransitionDurationStyle(options.duration, applyOnlyDuration);
+
+        // we set the duration so that it will be picked up by getComputedStyle later
+        applyInlineStyle(node, durationStyle);
+        temporaryStyles.push(durationStyle);
+      }
+
+      if (options.keyframeStyle) {
+        var keyframeStyle = [ANIMATION_PROP, options.keyframeStyle];
+        applyInlineStyle(node, keyframeStyle);
+        temporaryStyles.push(keyframeStyle);
+      }
+
+      var itemIndex = stagger
+          ? options.staggerIndex >= 0
+              ? options.staggerIndex
+              : gcsLookup.count(cacheKey)
+          : 0;
+
+      var isFirst = itemIndex === 0;
+
+      // this is a pre-emptive way of forcing the setup classes to be added and applied INSTANTLY
+      // without causing any combination of transitions to kick in. By adding a negative delay value
+      // it forces the setup class' transition to end immediately. We later then remove the negative
+      // transition delay to allow for the transition to naturally do it's thing. The beauty here is
+      // that if there is no transition defined then nothing will happen and this will also allow
+      // other transitions to be stacked on top of each other without any chopping them out.
+      if (isFirst && !options.skipBlocking) {
+        blockTransitions(node, SAFE_FAST_FORWARD_DURATION_VALUE);
+      }
+
+      var timings = computeTimings(node, fullClassName, cacheKey);
+      var relativeDelay = timings.maxDelay;
+      maxDelay = Math.max(relativeDelay, 0);
+      maxDuration = timings.maxDuration;
+
+      var flags = {};
+      flags.hasTransitions          = timings.transitionDuration > 0;
+      flags.hasAnimations           = timings.animationDuration > 0;
+      flags.hasTransitionAll        = flags.hasTransitions && timings.transitionProperty == 'all';
+      flags.applyTransitionDuration = hasToStyles && (
+                                        (flags.hasTransitions && !flags.hasTransitionAll)
+                                         || (flags.hasAnimations && !flags.hasTransitions));
+      flags.applyAnimationDuration  = options.duration && flags.hasAnimations;
+      flags.applyTransitionDelay    = truthyTimingValue(options.delay) && (flags.applyTransitionDuration || flags.hasTransitions);
+      flags.applyAnimationDelay     = truthyTimingValue(options.delay) && flags.hasAnimations;
+      flags.recalculateTimingStyles = addRemoveClassName.length > 0;
+
+      if (flags.applyTransitionDuration || flags.applyAnimationDuration) {
+        maxDuration = options.duration ? parseFloat(options.duration) : maxDuration;
+
+        if (flags.applyTransitionDuration) {
+          flags.hasTransitions = true;
+          timings.transitionDuration = maxDuration;
+          applyOnlyDuration = node.style[TRANSITION_PROP + PROPERTY_KEY].length > 0;
+          temporaryStyles.push(getCssTransitionDurationStyle(maxDuration, applyOnlyDuration));
+        }
+
+        if (flags.applyAnimationDuration) {
+          flags.hasAnimations = true;
+          timings.animationDuration = maxDuration;
+          temporaryStyles.push(getCssKeyframeDurationStyle(maxDuration));
+        }
+      }
+
+      if (maxDuration === 0 && !flags.recalculateTimingStyles) {
+        return closeAndReturnNoopAnimator();
+      }
+
+      if (options.delay != null) {
+        var delayStyle;
+        if (typeof options.delay !== "boolean") {
+          delayStyle = parseFloat(options.delay);
+          // number in options.delay means we have to recalculate the delay for the closing timeout
+          maxDelay = Math.max(delayStyle, 0);
+        }
+
+        if (flags.applyTransitionDelay) {
+          temporaryStyles.push(getCssDelayStyle(delayStyle));
+        }
+
+        if (flags.applyAnimationDelay) {
+          temporaryStyles.push(getCssDelayStyle(delayStyle, true));
+        }
+      }
+
+      // we need to recalculate the delay value since we used a pre-emptive negative
+      // delay value and the delay value is required for the final event checking. This
+      // property will ensure that this will happen after the RAF phase has passed.
+      if (options.duration == null && timings.transitionDuration > 0) {
+        flags.recalculateTimingStyles = flags.recalculateTimingStyles || isFirst;
+      }
+
+      maxDelayTime = maxDelay * ONE_SECOND;
+      maxDurationTime = maxDuration * ONE_SECOND;
+      if (!options.skipBlocking) {
+        flags.blockTransition = timings.transitionDuration > 0;
+        flags.blockKeyframeAnimation = timings.animationDuration > 0 &&
+                                       stagger.animationDelay > 0 &&
+                                       stagger.animationDuration === 0;
+      }
+
+      if (options.from) {
+        if (options.cleanupStyles) {
+          registerRestorableStyles(restoreStyles, node, Object.keys(options.from));
+        }
+        applyAnimationFromStyles(element, options);
+      }
+
+      if (flags.blockTransition || flags.blockKeyframeAnimation) {
+        applyBlocking(maxDuration);
+      } else if (!options.skipBlocking) {
+        blockTransitions(node, false);
+      }
+
+      // TODO(matsko): for 1.5 change this code to have an animator object for better debugging
+      return {
+        $$willAnimate: true,
+        end: endFn,
+        start: function() {
+          if (animationClosed) return;
+
+          runnerHost = {
+            end: endFn,
+            cancel: cancelFn,
+            resume: null, //this will be set during the start() phase
+            pause: null
+          };
+
+          runner = new $$AnimateRunner(runnerHost);
+
+          waitUntilQuiet(start);
+
+          // we don't have access to pause/resume the animation
+          // since it hasn't run yet. AnimateRunner will therefore
+          // set noop functions for resume and pause and they will
+          // later be overridden once the animation is triggered
+          return runner;
+        }
+      };
+
+      function endFn() {
+        close();
+      }
+
+      function cancelFn() {
+        close(true);
+      }
+
+      function close(rejected) { // jshint ignore:line
+        // if the promise has been called already then we shouldn't close
+        // the animation again
+        if (animationClosed || (animationCompleted && animationPaused)) return;
+        animationClosed = true;
+        animationPaused = false;
+
+        if (!options.$$skipPreparationClasses) {
+          $$jqLite.removeClass(element, preparationClasses);
+        }
+        $$jqLite.removeClass(element, activeClasses);
+
+        blockKeyframeAnimations(node, false);
+        blockTransitions(node, false);
+
+        forEach(temporaryStyles, function(entry) {
+          // There is only one way to remove inline style properties entirely from elements.
+          // By using `removeProperty` this works, but we need to convert camel-cased CSS
+          // styles down to hyphenated values.
+          node.style[entry[0]] = '';
+        });
+
+        applyAnimationClasses(element, options);
+        applyAnimationStyles(element, options);
+
+        if (Object.keys(restoreStyles).length) {
+          forEach(restoreStyles, function(value, prop) {
+            value ? node.style.setProperty(prop, value)
+                  : node.style.removeProperty(prop);
+          });
+        }
+
+        // the reason why we have this option is to allow a synchronous closing callback
+        // that is fired as SOON as the animation ends (when the CSS is removed) or if
+        // the animation never takes off at all. A good example is a leave animation since
+        // the element must be removed just after the animation is over or else the element
+        // will appear on screen for one animation frame causing an overbearing flicker.
+        if (options.onDone) {
+          options.onDone();
+        }
+
+        if (events && events.length) {
+          // Remove the transitionend / animationend listener(s)
+          element.off(events.join(' '), onAnimationProgress);
+        }
+
+        //Cancel the fallback closing timeout and remove the timer data
+        var animationTimerData = element.data(ANIMATE_TIMER_KEY);
+        if (animationTimerData) {
+          $timeout.cancel(animationTimerData[0].timer);
+          element.removeData(ANIMATE_TIMER_KEY);
+        }
+
+        // if the preparation function fails then the promise is not setup
+        if (runner) {
+          runner.complete(!rejected);
+        }
+      }
+
+      function applyBlocking(duration) {
+        if (flags.blockTransition) {
+          blockTransitions(node, duration);
+        }
+
+        if (flags.blockKeyframeAnimation) {
+          blockKeyframeAnimations(node, !!duration);
+        }
+      }
+
+      function closeAndReturnNoopAnimator() {
+        runner = new $$AnimateRunner({
+          end: endFn,
+          cancel: cancelFn
+        });
+
+        // should flush the cache animation
+        waitUntilQuiet(noop);
+        close();
+
+        return {
+          $$willAnimate: false,
+          start: function() {
+            return runner;
+          },
+          end: endFn
+        };
+      }
+
+      function onAnimationProgress(event) {
+        event.stopPropagation();
+        var ev = event.originalEvent || event;
+
+        // we now always use `Date.now()` due to the recent changes with
+        // event.timeStamp in Firefox, Webkit and Chrome (see #13494 for more info)
+        var timeStamp = ev.$manualTimeStamp || Date.now();
+
+        /* Firefox (or possibly just Gecko) likes to not round values up
+         * when a ms measurement is used for the animation */
+        var elapsedTime = parseFloat(ev.elapsedTime.toFixed(ELAPSED_TIME_MAX_DECIMAL_PLACES));
+
+        /* $manualTimeStamp is a mocked timeStamp value which is set
+         * within browserTrigger(). This is only here so that tests can
+         * mock animations properly. Real events fallback to event.timeStamp,
+         * or, if they don't, then a timeStamp is automatically created for them.
+         * We're checking to see if the timeStamp surpasses the expected delay,
+         * but we're using elapsedTime instead of the timeStamp on the 2nd
+         * pre-condition since animationPauseds sometimes close off early */
+        if (Math.max(timeStamp - startTime, 0) >= maxDelayTime && elapsedTime >= maxDuration) {
+          // we set this flag to ensure that if the transition is paused then, when resumed,
+          // the animation will automatically close itself since transitions cannot be paused.
+          animationCompleted = true;
+          close();
+        }
+      }
+
+      function start() {
+        if (animationClosed) return;
+        if (!node.parentNode) {
+          close();
+          return;
+        }
+
+        // even though we only pause keyframe animations here the pause flag
+        // will still happen when transitions are used. Only the transition will
+        // not be paused since that is not possible. If the animation ends when
+        // paused then it will not complete until unpaused or cancelled.
+        var playPause = function(playAnimation) {
+          if (!animationCompleted) {
+            animationPaused = !playAnimation;
+            if (timings.animationDuration) {
+              var value = blockKeyframeAnimations(node, animationPaused);
+              animationPaused
+                  ? temporaryStyles.push(value)
+                  : removeFromArray(temporaryStyles, value);
+            }
+          } else if (animationPaused && playAnimation) {
+            animationPaused = false;
+            close();
+          }
+        };
+
+        // checking the stagger duration prevents an accidentally cascade of the CSS delay style
+        // being inherited from the parent. If the transition duration is zero then we can safely
+        // rely that the delay value is an intentional stagger delay style.
+        var maxStagger = itemIndex > 0
+                         && ((timings.transitionDuration && stagger.transitionDuration === 0) ||
+                            (timings.animationDuration && stagger.animationDuration === 0))
+                         && Math.max(stagger.animationDelay, stagger.transitionDelay);
+        if (maxStagger) {
+          $timeout(triggerAnimationStart,
+                   Math.floor(maxStagger * itemIndex * ONE_SECOND),
+                   false);
+        } else {
+          triggerAnimationStart();
+        }
+
+        // this will decorate the existing promise runner with pause/resume methods
+        runnerHost.resume = function() {
+          playPause(true);
+        };
+
+        runnerHost.pause = function() {
+          playPause(false);
+        };
+
+        function triggerAnimationStart() {
+          // just incase a stagger animation kicks in when the animation
+          // itself was cancelled entirely
+          if (animationClosed) return;
+
+          applyBlocking(false);
+
+          forEach(temporaryStyles, function(entry) {
+            var key = entry[0];
+            var value = entry[1];
+            node.style[key] = value;
+          });
+
+          applyAnimationClasses(element, options);
+          $$jqLite.addClass(element, activeClasses);
+
+          if (flags.recalculateTimingStyles) {
+            fullClassName = node.className + ' ' + preparationClasses;
+            cacheKey = gcsHashFn(node, fullClassName);
+
+            timings = computeTimings(node, fullClassName, cacheKey);
+            relativeDelay = timings.maxDelay;
+            maxDelay = Math.max(relativeDelay, 0);
+            maxDuration = timings.maxDuration;
+
+            if (maxDuration === 0) {
+              close();
+              return;
+            }
+
+            flags.hasTransitions = timings.transitionDuration > 0;
+            flags.hasAnimations = timings.animationDuration > 0;
+          }
+
+          if (flags.applyAnimationDelay) {
+            relativeDelay = typeof options.delay !== "boolean" && truthyTimingValue(options.delay)
+                  ? parseFloat(options.delay)
+                  : relativeDelay;
+
+            maxDelay = Math.max(relativeDelay, 0);
+            timings.animationDelay = relativeDelay;
+            delayStyle = getCssDelayStyle(relativeDelay, true);
+            temporaryStyles.push(delayStyle);
+            node.style[delayStyle[0]] = delayStyle[1];
+          }
+
+          maxDelayTime = maxDelay * ONE_SECOND;
+          maxDurationTime = maxDuration * ONE_SECOND;
+
+          if (options.easing) {
+            var easeProp, easeVal = options.easing;
+            if (flags.hasTransitions) {
+              easeProp = TRANSITION_PROP + TIMING_KEY;
+              temporaryStyles.push([easeProp, easeVal]);
+              node.style[easeProp] = easeVal;
+            }
+            if (flags.hasAnimations) {
+              easeProp = ANIMATION_PROP + TIMING_KEY;
+              temporaryStyles.push([easeProp, easeVal]);
+              node.style[easeProp] = easeVal;
+            }
+          }
+
+          if (timings.transitionDuration) {
+            events.push(TRANSITIONEND_EVENT);
+          }
+
+          if (timings.animationDuration) {
+            events.push(ANIMATIONEND_EVENT);
+          }
+
+          startTime = Date.now();
+          var timerTime = maxDelayTime + CLOSING_TIME_BUFFER * maxDurationTime;
+          var endTime = startTime + timerTime;
+
+          var animationsData = element.data(ANIMATE_TIMER_KEY) || [];
+          var setupFallbackTimer = true;
+          if (animationsData.length) {
+            var currentTimerData = animationsData[0];
+            setupFallbackTimer = endTime > currentTimerData.expectedEndTime;
+            if (setupFallbackTimer) {
+              $timeout.cancel(currentTimerData.timer);
+            } else {
+              animationsData.push(close);
+            }
+          }
+
+          if (setupFallbackTimer) {
+            var timer = $timeout(onAnimationExpired, timerTime, false);
+            animationsData[0] = {
+              timer: timer,
+              expectedEndTime: endTime
+            };
+            animationsData.push(close);
+            element.data(ANIMATE_TIMER_KEY, animationsData);
+          }
+
+          if (events.length) {
+            element.on(events.join(' '), onAnimationProgress);
+          }
+
+          if (options.to) {
+            if (options.cleanupStyles) {
+              registerRestorableStyles(restoreStyles, node, Object.keys(options.to));
+            }
+            applyAnimationToStyles(element, options);
+          }
+        }
+
+        function onAnimationExpired() {
+          var animationsData = element.data(ANIMATE_TIMER_KEY);
+
+          // this will be false in the event that the element was
+          // removed from the DOM (via a leave animation or something
+          // similar)
+          if (animationsData) {
+            for (var i = 1; i < animationsData.length; i++) {
+              animationsData[i]();
+            }
+            element.removeData(ANIMATE_TIMER_KEY);
+          }
+        }
+      }
+    };
+  }];
+}];
+
+var $$AnimateCssDriverProvider = ['$$animationProvider', function($$animationProvider) {
+  $$animationProvider.drivers.push('$$animateCssDriver');
+
+  var NG_ANIMATE_SHIM_CLASS_NAME = 'ng-animate-shim';
+  var NG_ANIMATE_ANCHOR_CLASS_NAME = 'ng-anchor';
+
+  var NG_OUT_ANCHOR_CLASS_NAME = 'ng-anchor-out';
+  var NG_IN_ANCHOR_CLASS_NAME = 'ng-anchor-in';
+
+  function isDocumentFragment(node) {
+    return node.parentNode && node.parentNode.nodeType === 11;
+  }
+
+  this.$get = ['$animateCss', '$rootScope', '$$AnimateRunner', '$rootElement', '$sniffer', '$$jqLite', '$document',
+       function($animateCss,   $rootScope,   $$AnimateRunner,   $rootElement,   $sniffer,   $$jqLite,   $document) {
+
+    // only browsers that support these properties can render animations
+    if (!$sniffer.animations && !$sniffer.transitions) return noop;
+
+    var bodyNode = $document[0].body;
+    var rootNode = getDomNode($rootElement);
+
+    var rootBodyElement = jqLite(
+      // this is to avoid using something that exists outside of the body
+      // we also special case the doc fragment case because our unit test code
+      // appends the $rootElement to the body after the app has been bootstrapped
+      isDocumentFragment(rootNode) || bodyNode.contains(rootNode) ? rootNode : bodyNode
+    );
+
+    var applyAnimationClasses = applyAnimationClassesFactory($$jqLite);
+
+    return function initDriverFn(animationDetails) {
+      return animationDetails.from && animationDetails.to
+          ? prepareFromToAnchorAnimation(animationDetails.from,
+                                         animationDetails.to,
+                                         animationDetails.classes,
+                                         animationDetails.anchors)
+          : prepareRegularAnimation(animationDetails);
+    };
+
+    function filterCssClasses(classes) {
+      //remove all the `ng-` stuff
+      return classes.replace(/\bng-\S+\b/g, '');
+    }
+
+    function getUniqueValues(a, b) {
+      if (isString(a)) a = a.split(' ');
+      if (isString(b)) b = b.split(' ');
+      return a.filter(function(val) {
+        return b.indexOf(val) === -1;
+      }).join(' ');
+    }
+
+    function prepareAnchoredAnimation(classes, outAnchor, inAnchor) {
+      var clone = jqLite(getDomNode(outAnchor).cloneNode(true));
+      var startingClasses = filterCssClasses(getClassVal(clone));
+
+      outAnchor.addClass(NG_ANIMATE_SHIM_CLASS_NAME);
+      inAnchor.addClass(NG_ANIMATE_SHIM_CLASS_NAME);
+
+      clone.addClass(NG_ANIMATE_ANCHOR_CLASS_NAME);
+
+      rootBodyElement.append(clone);
+
+      var animatorIn, animatorOut = prepareOutAnimation();
+
+      // the user may not end up using the `out` animation and
+      // only making use of the `in` animation or vice-versa.
+      // In either case we should allow this and not assume the
+      // animation is over unless both animations are not used.
+      if (!animatorOut) {
+        animatorIn = prepareInAnimation();
+        if (!animatorIn) {
+          return end();
+        }
+      }
+
+      var startingAnimator = animatorOut || animatorIn;
+
+      return {
+        start: function() {
+          var runner;
+
+          var currentAnimation = startingAnimator.start();
+          currentAnimation.done(function() {
+            currentAnimation = null;
+            if (!animatorIn) {
+              animatorIn = prepareInAnimation();
+              if (animatorIn) {
+                currentAnimation = animatorIn.start();
+                currentAnimation.done(function() {
+                  currentAnimation = null;
+                  end();
+                  runner.complete();
+                });
+                return currentAnimation;
+              }
+            }
+            // in the event that there is no `in` animation
+            end();
+            runner.complete();
+          });
+
+          runner = new $$AnimateRunner({
+            end: endFn,
+            cancel: endFn
+          });
+
+          return runner;
+
+          function endFn() {
+            if (currentAnimation) {
+              currentAnimation.end();
+            }
+          }
+        }
+      };
+
+      function calculateAnchorStyles(anchor) {
+        var styles = {};
+
+        var coords = getDomNode(anchor).getBoundingClientRect();
+
+        // we iterate directly since safari messes up and doesn't return
+        // all the keys for the coords object when iterated
+        forEach(['width','height','top','left'], function(key) {
+          var value = coords[key];
+          switch (key) {
+            case 'top':
+              value += bodyNode.scrollTop;
+              break;
+            case 'left':
+              value += bodyNode.scrollLeft;
+              break;
+          }
+          styles[key] = Math.floor(value) + 'px';
+        });
+        return styles;
+      }
+
+      function prepareOutAnimation() {
+        var animator = $animateCss(clone, {
+          addClass: NG_OUT_ANCHOR_CLASS_NAME,
+          delay: true,
+          from: calculateAnchorStyles(outAnchor)
+        });
+
+        // read the comment within `prepareRegularAnimation` to understand
+        // why this check is necessary
+        return animator.$$willAnimate ? animator : null;
+      }
+
+      function getClassVal(element) {
+        return element.attr('class') || '';
+      }
+
+      function prepareInAnimation() {
+        var endingClasses = filterCssClasses(getClassVal(inAnchor));
+        var toAdd = getUniqueValues(endingClasses, startingClasses);
+        var toRemove = getUniqueValues(startingClasses, endingClasses);
+
+        var animator = $animateCss(clone, {
+          to: calculateAnchorStyles(inAnchor),
+          addClass: NG_IN_ANCHOR_CLASS_NAME + ' ' + toAdd,
+          removeClass: NG_OUT_ANCHOR_CLASS_NAME + ' ' + toRemove,
+          delay: true
+        });
+
+        // read the comment within `prepareRegularAnimation` to understand
+        // why this check is necessary
+        return animator.$$willAnimate ? animator : null;
+      }
+
+      function end() {
+        clone.remove();
+        outAnchor.removeClass(NG_ANIMATE_SHIM_CLASS_NAME);
+        inAnchor.removeClass(NG_ANIMATE_SHIM_CLASS_NAME);
+      }
+    }
+
+    function prepareFromToAnchorAnimation(from, to, classes, anchors) {
+      var fromAnimation = prepareRegularAnimation(from, noop);
+      var toAnimation = prepareRegularAnimation(to, noop);
+
+      var anchorAnimations = [];
+      forEach(anchors, function(anchor) {
+        var outElement = anchor['out'];
+        var inElement = anchor['in'];
+        var animator = prepareAnchoredAnimation(classes, outElement, inElement);
+        if (animator) {
+          anchorAnimations.push(animator);
+        }
+      });
+
+      // no point in doing anything when there are no elements to animate
+      if (!fromAnimation && !toAnimation && anchorAnimations.length === 0) return;
+
+      return {
+        start: function() {
+          var animationRunners = [];
+
+          if (fromAnimation) {
+            animationRunners.push(fromAnimation.start());
+          }
+
+          if (toAnimation) {
+            animationRunners.push(toAnimation.start());
+          }
+
+          forEach(anchorAnimations, function(animation) {
+            animationRunners.push(animation.start());
+          });
+
+          var runner = new $$AnimateRunner({
+            end: endFn,
+            cancel: endFn // CSS-driven animations cannot be cancelled, only ended
+          });
+
+          $$AnimateRunner.all(animationRunners, function(status) {
+            runner.complete(status);
+          });
+
+          return runner;
+
+          function endFn() {
+            forEach(animationRunners, function(runner) {
+              runner.end();
+            });
+          }
+        }
+      };
+    }
+
+    function prepareRegularAnimation(animationDetails) {
+      var element = animationDetails.element;
+      var options = animationDetails.options || {};
+
+      if (animationDetails.structural) {
+        options.event = animationDetails.event;
+        options.structural = true;
+        options.applyClassesEarly = true;
+
+        // we special case the leave animation since we want to ensure that
+        // the element is removed as soon as the animation is over. Otherwise
+        // a flicker might appear or the element may not be removed at all
+        if (animationDetails.event === 'leave') {
+          options.onDone = options.domOperation;
+        }
+      }
+
+      // We assign the preparationClasses as the actual animation event since
+      // the internals of $animateCss will just suffix the event token values
+      // with `-active` to trigger the animation.
+      if (options.preparationClasses) {
+        options.event = concatWithSpace(options.event, options.preparationClasses);
+      }
+
+      var animator = $animateCss(element, options);
+
+      // the driver lookup code inside of $$animation attempts to spawn a
+      // driver one by one until a driver returns a.$$willAnimate animator object.
+      // $animateCss will always return an object, however, it will pass in
+      // a flag as a hint as to whether an animation was detected or not
+      return animator.$$willAnimate ? animator : null;
+    }
+  }];
+}];
+
+// TODO(matsko): use caching here to speed things up for detection
+// TODO(matsko): add documentation
+//  by the time...
+
+var $$AnimateJsProvider = ['$animateProvider', function($animateProvider) {
+  this.$get = ['$injector', '$$AnimateRunner', '$$jqLite',
+       function($injector,   $$AnimateRunner,   $$jqLite) {
+
+    var applyAnimationClasses = applyAnimationClassesFactory($$jqLite);
+         // $animateJs(element, 'enter');
+    return function(element, event, classes, options) {
+      var animationClosed = false;
+
+      // the `classes` argument is optional and if it is not used
+      // then the classes will be resolved from the element's className
+      // property as well as options.addClass/options.removeClass.
+      if (arguments.length === 3 && isObject(classes)) {
+        options = classes;
+        classes = null;
+      }
+
+      options = prepareAnimationOptions(options);
+      if (!classes) {
+        classes = element.attr('class') || '';
+        if (options.addClass) {
+          classes += ' ' + options.addClass;
+        }
+        if (options.removeClass) {
+          classes += ' ' + options.removeClass;
+        }
+      }
+
+      var classesToAdd = options.addClass;
+      var classesToRemove = options.removeClass;
+
+      // the lookupAnimations function returns a series of animation objects that are
+      // matched up with one or more of the CSS classes. These animation objects are
+      // defined via the module.animation factory function. If nothing is detected then
+      // we don't return anything which then makes $animation query the next driver.
+      var animations = lookupAnimations(classes);
+      var before, after;
+      if (animations.length) {
+        var afterFn, beforeFn;
+        if (event == 'leave') {
+          beforeFn = 'leave';
+          afterFn = 'afterLeave'; // TODO(matsko): get rid of this
+        } else {
+          beforeFn = 'before' + event.charAt(0).toUpperCase() + event.substr(1);
+          afterFn = event;
+        }
+
+        if (event !== 'enter' && event !== 'move') {
+          before = packageAnimations(element, event, options, animations, beforeFn);
+        }
+        after  = packageAnimations(element, event, options, animations, afterFn);
+      }
+
+      // no matching animations
+      if (!before && !after) return;
+
+      function applyOptions() {
+        options.domOperation();
+        applyAnimationClasses(element, options);
+      }
+
+      function close() {
+        animationClosed = true;
+        applyOptions();
+        applyAnimationStyles(element, options);
+      }
+
+      var runner;
+
+      return {
+        $$willAnimate: true,
+        end: function() {
+          if (runner) {
+            runner.end();
+          } else {
+            close();
+            runner = new $$AnimateRunner();
+            runner.complete(true);
+          }
+          return runner;
+        },
+        start: function() {
+          if (runner) {
+            return runner;
+          }
+
+          runner = new $$AnimateRunner();
+          var closeActiveAnimations;
+          var chain = [];
+
+          if (before) {
+            chain.push(function(fn) {
+              closeActiveAnimations = before(fn);
+            });
+          }
+
+          if (chain.length) {
+            chain.push(function(fn) {
+              applyOptions();
+              fn(true);
+            });
+          } else {
+            applyOptions();
+          }
+
+          if (after) {
+            chain.push(function(fn) {
+              closeActiveAnimations = after(fn);
+            });
+          }
+
+          runner.setHost({
+            end: function() {
+              endAnimations();
+            },
+            cancel: function() {
+              endAnimations(true);
+            }
+          });
+
+          $$AnimateRunner.chain(chain, onComplete);
+          return runner;
+
+          function onComplete(success) {
+            close(success);
+            runner.complete(success);
+          }
+
+          function endAnimations(cancelled) {
+            if (!animationClosed) {
+              (closeActiveAnimations || noop)(cancelled);
+              onComplete(cancelled);
+            }
+          }
+        }
+      };
+
+      function executeAnimationFn(fn, element, event, options, onDone) {
+        var args;
+        switch (event) {
+          case 'animate':
+            args = [element, options.from, options.to, onDone];
+            break;
+
+          case 'setClass':
+            args = [element, classesToAdd, classesToRemove, onDone];
+            break;
+
+          case 'addClass':
+            args = [element, classesToAdd, onDone];
+            break;
+
+          case 'removeClass':
+            args = [element, classesToRemove, onDone];
+            break;
+
+          default:
+            args = [element, onDone];
+            break;
+        }
+
+        args.push(options);
+
+        var value = fn.apply(fn, args);
+        if (value) {
+          if (isFunction(value.start)) {
+            value = value.start();
+          }
+
+          if (value instanceof $$AnimateRunner) {
+            value.done(onDone);
+          } else if (isFunction(value)) {
+            // optional onEnd / onCancel callback
+            return value;
+          }
+        }
+
+        return noop;
+      }
+
+      function groupEventedAnimations(element, event, options, animations, fnName) {
+        var operations = [];
+        forEach(animations, function(ani) {
+          var animation = ani[fnName];
+          if (!animation) return;
+
+          // note that all of these animations will run in parallel
+          operations.push(function() {
+            var runner;
+            var endProgressCb;
+
+            var resolved = false;
+            var onAnimationComplete = function(rejected) {
+              if (!resolved) {
+                resolved = true;
+                (endProgressCb || noop)(rejected);
+                runner.complete(!rejected);
+              }
+            };
+
+            runner = new $$AnimateRunner({
+              end: function() {
+                onAnimationComplete();
+              },
+              cancel: function() {
+                onAnimationComplete(true);
+              }
+            });
+
+            endProgressCb = executeAnimationFn(animation, element, event, options, function(result) {
+              var cancelled = result === false;
+              onAnimationComplete(cancelled);
+            });
+
+            return runner;
+          });
+        });
+
+        return operations;
+      }
+
+      function packageAnimations(element, event, options, animations, fnName) {
+        var operations = groupEventedAnimations(element, event, options, animations, fnName);
+        if (operations.length === 0) {
+          var a,b;
+          if (fnName === 'beforeSetClass') {
+            a = groupEventedAnimations(element, 'removeClass', options, animations, 'beforeRemoveClass');
+            b = groupEventedAnimations(element, 'addClass', options, animations, 'beforeAddClass');
+          } else if (fnName === 'setClass') {
+            a = groupEventedAnimations(element, 'removeClass', options, animations, 'removeClass');
+            b = groupEventedAnimations(element, 'addClass', options, animations, 'addClass');
+          }
+
+          if (a) {
+            operations = operations.concat(a);
+          }
+          if (b) {
+            operations = operations.concat(b);
+          }
+        }
+
+        if (operations.length === 0) return;
+
+        // TODO(matsko): add documentation
+        return function startAnimation(callback) {
+          var runners = [];
+          if (operations.length) {
+            forEach(operations, function(animateFn) {
+              runners.push(animateFn());
+            });
+          }
+
+          runners.length ? $$AnimateRunner.all(runners, callback) : callback();
+
+          return function endFn(reject) {
+            forEach(runners, function(runner) {
+              reject ? runner.cancel() : runner.end();
+            });
+          };
+        };
+      }
+    };
+
+    function lookupAnimations(classes) {
+      classes = isArray(classes) ? classes : classes.split(' ');
+      var matches = [], flagMap = {};
+      for (var i=0; i < classes.length; i++) {
+        var klass = classes[i],
+            animationFactory = $animateProvider.$$registeredAnimations[klass];
+        if (animationFactory && !flagMap[klass]) {
+          matches.push($injector.get(animationFactory));
+          flagMap[klass] = true;
+        }
+      }
+      return matches;
+    }
+  }];
+}];
+
+var $$AnimateJsDriverProvider = ['$$animationProvider', function($$animationProvider) {
+  $$animationProvider.drivers.push('$$animateJsDriver');
+  this.$get = ['$$animateJs', '$$AnimateRunner', function($$animateJs, $$AnimateRunner) {
+    return function initDriverFn(animationDetails) {
+      if (animationDetails.from && animationDetails.to) {
+        var fromAnimation = prepareAnimation(animationDetails.from);
+        var toAnimation = prepareAnimation(animationDetails.to);
+        if (!fromAnimation && !toAnimation) return;
+
+        return {
+          start: function() {
+            var animationRunners = [];
+
+            if (fromAnimation) {
+              animationRunners.push(fromAnimation.start());
+            }
+
+            if (toAnimation) {
+              animationRunners.push(toAnimation.start());
+            }
+
+            $$AnimateRunner.all(animationRunners, done);
+
+            var runner = new $$AnimateRunner({
+              end: endFnFactory(),
+              cancel: endFnFactory()
+            });
+
+            return runner;
+
+            function endFnFactory() {
+              return function() {
+                forEach(animationRunners, function(runner) {
+                  // at this point we cannot cancel animations for groups just yet. 1.5+
+                  runner.end();
+                });
+              };
+            }
+
+            function done(status) {
+              runner.complete(status);
+            }
+          }
+        };
+      } else {
+        return prepareAnimation(animationDetails);
+      }
+    };
+
+    function prepareAnimation(animationDetails) {
+      // TODO(matsko): make sure to check for grouped animations and delegate down to normal animations
+      var element = animationDetails.element;
+      var event = animationDetails.event;
+      var options = animationDetails.options;
+      var classes = animationDetails.classes;
+      return $$animateJs(element, event, classes, options);
+    }
+  }];
+}];
+
+var NG_ANIMATE_ATTR_NAME = 'data-ng-animate';
+var NG_ANIMATE_PIN_DATA = '$ngAnimatePin';
+var $$AnimateQueueProvider = ['$animateProvider', function($animateProvider) {
+  var PRE_DIGEST_STATE = 1;
+  var RUNNING_STATE = 2;
+  var ONE_SPACE = ' ';
+
+  var rules = this.rules = {
+    skip: [],
+    cancel: [],
+    join: []
+  };
+
+  function makeTruthyCssClassMap(classString) {
+    if (!classString) {
+      return null;
+    }
+
+    var keys = classString.split(ONE_SPACE);
+    var map = Object.create(null);
+
+    forEach(keys, function(key) {
+      map[key] = true;
+    });
+    return map;
+  }
+
+  function hasMatchingClasses(newClassString, currentClassString) {
+    if (newClassString && currentClassString) {
+      var currentClassMap = makeTruthyCssClassMap(currentClassString);
+      return newClassString.split(ONE_SPACE).some(function(className) {
+        return currentClassMap[className];
+      });
+    }
+  }
+
+  function isAllowed(ruleType, element, currentAnimation, previousAnimation) {
+    return rules[ruleType].some(function(fn) {
+      return fn(element, currentAnimation, previousAnimation);
+    });
+  }
+
+  function hasAnimationClasses(animation, and) {
+    var a = (animation.addClass || '').length > 0;
+    var b = (animation.removeClass || '').length > 0;
+    return and ? a && b : a || b;
+  }
+
+  rules.join.push(function(element, newAnimation, currentAnimation) {
+    // if the new animation is class-based then we can just tack that on
+    return !newAnimation.structural && hasAnimationClasses(newAnimation);
+  });
+
+  rules.skip.push(function(element, newAnimation, currentAnimation) {
+    // there is no need to animate anything if no classes are being added and
+    // there is no structural animation that will be triggered
+    return !newAnimation.structural && !hasAnimationClasses(newAnimation);
+  });
+
+  rules.skip.push(function(element, newAnimation, currentAnimation) {
+    // why should we trigger a new structural animation if the element will
+    // be removed from the DOM anyway?
+    return currentAnimation.event == 'leave' && newAnimation.structural;
+  });
+
+  rules.skip.push(function(element, newAnimation, currentAnimation) {
+    // if there is an ongoing current animation then don't even bother running the class-based animation
+    return currentAnimation.structural && currentAnimation.state === RUNNING_STATE && !newAnimation.structural;
+  });
+
+  rules.cancel.push(function(element, newAnimation, currentAnimation) {
+    // there can never be two structural animations running at the same time
+    return currentAnimation.structural && newAnimation.structural;
+  });
+
+  rules.cancel.push(function(element, newAnimation, currentAnimation) {
+    // if the previous animation is already running, but the new animation will
+    // be triggered, but the new animation is structural
+    return currentAnimation.state === RUNNING_STATE && newAnimation.structural;
+  });
+
+  rules.cancel.push(function(element, newAnimation, currentAnimation) {
+    // cancel the animation if classes added / removed in both animation cancel each other out,
+    // but only if the current animation isn't structural
+
+    if (currentAnimation.structural) return false;
+
+    var nA = newAnimation.addClass;
+    var nR = newAnimation.removeClass;
+    var cA = currentAnimation.addClass;
+    var cR = currentAnimation.removeClass;
+
+    // early detection to save the global CPU shortage :)
+    if ((isUndefined(nA) && isUndefined(nR)) || (isUndefined(cA) && isUndefined(cR))) {
+      return false;
+    }
+
+    return hasMatchingClasses(nA, cR) || hasMatchingClasses(nR, cA);
+  });
+
+  this.$get = ['$$rAF', '$rootScope', '$rootElement', '$document', '$$HashMap',
+               '$$animation', '$$AnimateRunner', '$templateRequest', '$$jqLite', '$$forceReflow',
+       function($$rAF,   $rootScope,   $rootElement,   $document,   $$HashMap,
+                $$animation,   $$AnimateRunner,   $templateRequest,   $$jqLite,   $$forceReflow) {
+
+    var activeAnimationsLookup = new $$HashMap();
+    var disabledElementsLookup = new $$HashMap();
+    var animationsEnabled = null;
+
+    function postDigestTaskFactory() {
+      var postDigestCalled = false;
+      return function(fn) {
+        // we only issue a call to postDigest before
+        // it has first passed. This prevents any callbacks
+        // from not firing once the animation has completed
+        // since it will be out of the digest cycle.
+        if (postDigestCalled) {
+          fn();
+        } else {
+          $rootScope.$$postDigest(function() {
+            postDigestCalled = true;
+            fn();
+          });
+        }
+      };
+    }
+
+    // Wait until all directive and route-related templates are downloaded and
+    // compiled. The $templateRequest.totalPendingRequests variable keeps track of
+    // all of the remote templates being currently downloaded. If there are no
+    // templates currently downloading then the watcher will still fire anyway.
+    var deregisterWatch = $rootScope.$watch(
+      function() { return $templateRequest.totalPendingRequests === 0; },
+      function(isEmpty) {
+        if (!isEmpty) return;
+        deregisterWatch();
+
+        // Now that all templates have been downloaded, $animate will wait until
+        // the post digest queue is empty before enabling animations. By having two
+        // calls to $postDigest calls we can ensure that the flag is enabled at the
+        // very end of the post digest queue. Since all of the animations in $animate
+        // use $postDigest, it's important that the code below executes at the end.
+        // This basically means that the page is fully downloaded and compiled before
+        // any animations are triggered.
+        $rootScope.$$postDigest(function() {
+          $rootScope.$$postDigest(function() {
+            // we check for null directly in the event that the application already called
+            // .enabled() with whatever arguments that it provided it with
+            if (animationsEnabled === null) {
+              animationsEnabled = true;
+            }
+          });
+        });
+      }
+    );
+
+    var callbackRegistry = Object.create(null);
+
+    // remember that the classNameFilter is set during the provider/config
+    // stage therefore we can optimize here and setup a helper function
+    var classNameFilter = $animateProvider.classNameFilter();
+    var isAnimatableClassName = !classNameFilter
+              ? function() { return true; }
+              : function(className) {
+                return classNameFilter.test(className);
+              };
+
+    var applyAnimationClasses = applyAnimationClassesFactory($$jqLite);
+
+    function normalizeAnimationDetails(element, animation) {
+      return mergeAnimationDetails(element, animation, {});
+    }
+
+    // IE9-11 has no method "contains" in SVG element and in Node.prototype. Bug #10259.
+    var contains = window.Node.prototype.contains || function(arg) {
+      // jshint bitwise: false
+      return this === arg || !!(this.compareDocumentPosition(arg) & 16);
+      // jshint bitwise: true
+    };
+
+    function findCallbacks(parent, element, event) {
+      var targetNode = getDomNode(element);
+      var targetParentNode = getDomNode(parent);
+
+      var matches = [];
+      var entries = callbackRegistry[event];
+      if (entries) {
+        forEach(entries, function(entry) {
+          if (contains.call(entry.node, targetNode)) {
+            matches.push(entry.callback);
+          } else if (event === 'leave' && contains.call(entry.node, targetParentNode)) {
+            matches.push(entry.callback);
+          }
+        });
+      }
+
+      return matches;
+    }
+
+    function filterFromRegistry(list, matchContainer, matchCallback) {
+      var containerNode = extractElementNode(matchContainer);
+      return list.filter(function(entry) {
+        var isMatch = entry.node === containerNode &&
+                        (!matchCallback || entry.callback === matchCallback);
+        return !isMatch;
+      });
+    }
+
+    function cleanupEventListeners(phase, element) {
+      if (phase === 'close' && !element[0].parentNode) {
+        // If the element is not attached to a parentNode, it has been removed by
+        // the domOperation, and we can safely remove the event callbacks
+        $animate.off(element);
+      }
+    }
+
+    var $animate = {
+      on: function(event, container, callback) {
+        var node = extractElementNode(container);
+        callbackRegistry[event] = callbackRegistry[event] || [];
+        callbackRegistry[event].push({
+          node: node,
+          callback: callback
+        });
+
+        // Remove the callback when the element is removed from the DOM
+        jqLite(container).on('$destroy', function() {
+          var animationDetails = activeAnimationsLookup.get(node);
+
+          if (!animationDetails) {
+            // If there's an animation ongoing, the callback calling code will remove
+            // the event listeners. If we'd remove here, the callbacks would be removed
+            // before the animation ends
+            $animate.off(event, container, callback);
+          }
+        });
+      },
+
+      off: function(event, container, callback) {
+        if (arguments.length === 1 && !isString(arguments[0])) {
+          container = arguments[0];
+          for (var eventType in callbackRegistry) {
+            callbackRegistry[eventType] = filterFromRegistry(callbackRegistry[eventType], container);
+          }
+
+          return;
+        }
+
+        var entries = callbackRegistry[event];
+        if (!entries) return;
+
+        callbackRegistry[event] = arguments.length === 1
+            ? null
+            : filterFromRegistry(entries, container, callback);
+      },
+
+      pin: function(element, parentElement) {
+        assertArg(isElement(element), 'element', 'not an element');
+        assertArg(isElement(parentElement), 'parentElement', 'not an element');
+        element.data(NG_ANIMATE_PIN_DATA, parentElement);
+      },
+
+      push: function(element, event, options, domOperation) {
+        options = options || {};
+        options.domOperation = domOperation;
+        return queueAnimation(element, event, options);
+      },
+
+      // this method has four signatures:
+      //  () - global getter
+      //  (bool) - global setter
+      //  (element) - element getter
+      //  (element, bool) - element setter<F37>
+      enabled: function(element, bool) {
+        var argCount = arguments.length;
+
+        if (argCount === 0) {
+          // () - Global getter
+          bool = !!animationsEnabled;
+        } else {
+          var hasElement = isElement(element);
+
+          if (!hasElement) {
+            // (bool) - Global setter
+            bool = animationsEnabled = !!element;
+          } else {
+            var node = getDomNode(element);
+
+            if (argCount === 1) {
+              // (element) - Element getter
+              bool = !disabledElementsLookup.get(node);
+            } else {
+              // (element, bool) - Element setter
+              disabledElementsLookup.put(node, !bool);
+            }
+          }
+        }
+
+        return bool;
+      }
+    };
+
+    return $animate;
+
+    function queueAnimation(element, event, initialOptions) {
+      // we always make a copy of the options since
+      // there should never be any side effects on
+      // the input data when running `$animateCss`.
+      var options = copy(initialOptions);
+
+      var node, parent;
+      element = stripCommentsFromElement(element);
+      if (element) {
+        node = getDomNode(element);
+        parent = element.parent();
+      }
+
+      options = prepareAnimationOptions(options);
+
+      // we create a fake runner with a working promise.
+      // These methods will become available after the digest has passed
+      var runner = new $$AnimateRunner();
+
+      // this is used to trigger callbacks in postDigest mode
+      var runInNextPostDigestOrNow = postDigestTaskFactory();
+
+      if (isArray(options.addClass)) {
+        options.addClass = options.addClass.join(' ');
+      }
+
+      if (options.addClass && !isString(options.addClass)) {
+        options.addClass = null;
+      }
+
+      if (isArray(options.removeClass)) {
+        options.removeClass = options.removeClass.join(' ');
+      }
+
+      if (options.removeClass && !isString(options.removeClass)) {
+        options.removeClass = null;
+      }
+
+      if (options.from && !isObject(options.from)) {
+        options.from = null;
+      }
+
+      if (options.to && !isObject(options.to)) {
+        options.to = null;
+      }
+
+      // there are situations where a directive issues an animation for
+      // a jqLite wrapper that contains only comment nodes... If this
+      // happens then there is no way we can perform an animation
+      if (!node) {
+        close();
+        return runner;
+      }
+
+      var className = [node.className, options.addClass, options.removeClass].join(' ');
+      if (!isAnimatableClassName(className)) {
+        close();
+        return runner;
+      }
+
+      var isStructural = ['enter', 'move', 'leave'].indexOf(event) >= 0;
+
+      var documentHidden = $document[0].hidden;
+
+      // this is a hard disable of all animations for the application or on
+      // the element itself, therefore  there is no need to continue further
+      // past this point if not enabled
+      // Animations are also disabled if the document is currently hidden (page is not visible
+      // to the user), because browsers slow down or do not flush calls to requestAnimationFrame
+      var skipAnimations = !animationsEnabled || documentHidden || disabledElementsLookup.get(node);
+      var existingAnimation = (!skipAnimations && activeAnimationsLookup.get(node)) || {};
+      var hasExistingAnimation = !!existingAnimation.state;
+
+      // there is no point in traversing the same collection of parent ancestors if a followup
+      // animation will be run on the same element that already did all that checking work
+      if (!skipAnimations && (!hasExistingAnimation || existingAnimation.state != PRE_DIGEST_STATE)) {
+        skipAnimations = !areAnimationsAllowed(element, parent, event);
+      }
+
+      if (skipAnimations) {
+        // Callbacks should fire even if the document is hidden (regression fix for issue #14120)
+        if (documentHidden) notifyProgress(runner, event, 'start');
+        close();
+        if (documentHidden) notifyProgress(runner, event, 'close');
+        return runner;
+      }
+
+      if (isStructural) {
+        closeChildAnimations(element);
+      }
+
+      var newAnimation = {
+        structural: isStructural,
+        element: element,
+        event: event,
+        addClass: options.addClass,
+        removeClass: options.removeClass,
+        close: close,
+        options: options,
+        runner: runner
+      };
+
+      if (hasExistingAnimation) {
+        var skipAnimationFlag = isAllowed('skip', element, newAnimation, existingAnimation);
+        if (skipAnimationFlag) {
+          if (existingAnimation.state === RUNNING_STATE) {
+            close();
+            return runner;
+          } else {
+            mergeAnimationDetails(element, existingAnimation, newAnimation);
+            return existingAnimation.runner;
+          }
+        }
+        var cancelAnimationFlag = isAllowed('cancel', element, newAnimation, existingAnimation);
+        if (cancelAnimationFlag) {
+          if (existingAnimation.state === RUNNING_STATE) {
+            // this will end the animation right away and it is safe
+            // to do so since the animation is already running and the
+            // runner callback code will run in async
+            existingAnimation.runner.end();
+          } else if (existingAnimation.structural) {
+            // this means that the animation is queued into a digest, but
+            // hasn't started yet. Therefore it is safe to run the close
+            // method which will call the runner methods in async.
+            existingAnimation.close();
+          } else {
+            // this will merge the new animation options into existing animation options
+            mergeAnimationDetails(element, existingAnimation, newAnimation);
+
+            return existingAnimation.runner;
+          }
+        } else {
+          // a joined animation means that this animation will take over the existing one
+          // so an example would involve a leave animation taking over an enter. Then when
+          // the postDigest kicks in the enter will be ignored.
+          var joinAnimationFlag = isAllowed('join', element, newAnimation, existingAnimation);
+          if (joinAnimationFlag) {
+            if (existingAnimation.state === RUNNING_STATE) {
+              normalizeAnimationDetails(element, newAnimation);
+            } else {
+              applyGeneratedPreparationClasses(element, isStructural ? event : null, options);
+
+              event = newAnimation.event = existingAnimation.event;
+              options = mergeAnimationDetails(element, existingAnimation, newAnimation);
+
+              //we return the same runner since only the option values of this animation will
+              //be fed into the `existingAnimation`.
+              return existingAnimation.runner;
+            }
+          }
+        }
+      } else {
+        // normalization in this case means that it removes redundant CSS classes that
+        // already exist (addClass) or do not exist (removeClass) on the element
+        normalizeAnimationDetails(element, newAnimation);
+      }
+
+      // when the options are merged and cleaned up we may end up not having to do
+      // an animation at all, therefore we should check this before issuing a post
+      // digest callback. Structural animations will always run no matter what.
+      var isValidAnimation = newAnimation.structural;
+      if (!isValidAnimation) {
+        // animate (from/to) can be quickly checked first, otherwise we check if any classes are present
+        isValidAnimation = (newAnimation.event === 'animate' && Object.keys(newAnimation.options.to || {}).length > 0)
+                            || hasAnimationClasses(newAnimation);
+      }
+
+      if (!isValidAnimation) {
+        close();
+        clearElementAnimationState(element);
+        return runner;
+      }
+
+      // the counter keeps track of cancelled animations
+      var counter = (existingAnimation.counter || 0) + 1;
+      newAnimation.counter = counter;
+
+      markElementAnimationState(element, PRE_DIGEST_STATE, newAnimation);
+
+      $rootScope.$$postDigest(function() {
+        var animationDetails = activeAnimationsLookup.get(node);
+        var animationCancelled = !animationDetails;
+        animationDetails = animationDetails || {};
+
+        // if addClass/removeClass is called before something like enter then the
+        // registered parent element may not be present. The code below will ensure
+        // that a final value for parent element is obtained
+        var parentElement = element.parent() || [];
+
+        // animate/structural/class-based animations all have requirements. Otherwise there
+        // is no point in performing an animation. The parent node must also be set.
+        var isValidAnimation = parentElement.length > 0
+                                && (animationDetails.event === 'animate'
+                                    || animationDetails.structural
+                                    || hasAnimationClasses(animationDetails));
+
+        // this means that the previous animation was cancelled
+        // even if the follow-up animation is the same event
+        if (animationCancelled || animationDetails.counter !== counter || !isValidAnimation) {
+          // if another animation did not take over then we need
+          // to make sure that the domOperation and options are
+          // handled accordingly
+          if (animationCancelled) {
+            applyAnimationClasses(element, options);
+            applyAnimationStyles(element, options);
+          }
+
+          // if the event changed from something like enter to leave then we do
+          // it, otherwise if it's the same then the end result will be the same too
+          if (animationCancelled || (isStructural && animationDetails.event !== event)) {
+            options.domOperation();
+            runner.end();
+          }
+
+          // in the event that the element animation was not cancelled or a follow-up animation
+          // isn't allowed to animate from here then we need to clear the state of the element
+          // so that any future animations won't read the expired animation data.
+          if (!isValidAnimation) {
+            clearElementAnimationState(element);
+          }
+
+          return;
+        }
+
+        // this combined multiple class to addClass / removeClass into a setClass event
+        // so long as a structural event did not take over the animation
+        event = !animationDetails.structural && hasAnimationClasses(animationDetails, true)
+            ? 'setClass'
+            : animationDetails.event;
+
+        markElementAnimationState(element, RUNNING_STATE);
+        var realRunner = $$animation(element, event, animationDetails.options);
+
+        // this will update the runner's flow-control events based on
+        // the `realRunner` object.
+        runner.setHost(realRunner);
+        notifyProgress(runner, event, 'start', {});
+
+        realRunner.done(function(status) {
+          close(!status);
+          var animationDetails = activeAnimationsLookup.get(node);
+          if (animationDetails && animationDetails.counter === counter) {
+            clearElementAnimationState(getDomNode(element));
+          }
+          notifyProgress(runner, event, 'close', {});
+        });
+      });
+
+      return runner;
+
+      function notifyProgress(runner, event, phase, data) {
+        runInNextPostDigestOrNow(function() {
+          var callbacks = findCallbacks(parent, element, event);
+          if (callbacks.length) {
+            // do not optimize this call here to RAF because
+            // we don't know how heavy the callback code here will
+            // be and if this code is buffered then this can
+            // lead to a performance regression.
+            $$rAF(function() {
+              forEach(callbacks, function(callback) {
+                callback(element, phase, data);
+              });
+              cleanupEventListeners(phase, element);
+            });
+          } else {
+            cleanupEventListeners(phase, element);
+          }
+        });
+        runner.progress(event, phase, data);
+      }
+
+      function close(reject) { // jshint ignore:line
+        clearGeneratedClasses(element, options);
+        applyAnimationClasses(element, options);
+        applyAnimationStyles(element, options);
+        options.domOperation();
+        runner.complete(!reject);
+      }
+    }
+
+    function closeChildAnimations(element) {
+      var node = getDomNode(element);
+      var children = node.querySelectorAll('[' + NG_ANIMATE_ATTR_NAME + ']');
+      forEach(children, function(child) {
+        var state = parseInt(child.getAttribute(NG_ANIMATE_ATTR_NAME));
+        var animationDetails = activeAnimationsLookup.get(child);
+        if (animationDetails) {
+          switch (state) {
+            case RUNNING_STATE:
+              animationDetails.runner.end();
+              /* falls through */
+            case PRE_DIGEST_STATE:
+              activeAnimationsLookup.remove(child);
+              break;
+          }
+        }
+      });
+    }
+
+    function clearElementAnimationState(element) {
+      var node = getDomNode(element);
+      node.removeAttribute(NG_ANIMATE_ATTR_NAME);
+      activeAnimationsLookup.remove(node);
+    }
+
+    function isMatchingElement(nodeOrElmA, nodeOrElmB) {
+      return getDomNode(nodeOrElmA) === getDomNode(nodeOrElmB);
+    }
+
+    /**
+     * This fn returns false if any of the following is true:
+     * a) animations on any parent element are disabled, and animations on the element aren't explicitly allowed
+     * b) a parent element has an ongoing structural animation, and animateChildren is false
+     * c) the element is not a child of the body
+     * d) the element is not a child of the $rootElement
+     */
+    function areAnimationsAllowed(element, parentElement, event) {
+      var bodyElement = jqLite($document[0].body);
+      var bodyElementDetected = isMatchingElement(element, bodyElement) || element[0].nodeName === 'HTML';
+      var rootElementDetected = isMatchingElement(element, $rootElement);
+      var parentAnimationDetected = false;
+      var animateChildren;
+      var elementDisabled = disabledElementsLookup.get(getDomNode(element));
+
+      var parentHost = jqLite.data(element[0], NG_ANIMATE_PIN_DATA);
+      if (parentHost) {
+        parentElement = parentHost;
+      }
+
+      parentElement = getDomNode(parentElement);
+
+      while (parentElement) {
+        if (!rootElementDetected) {
+          // angular doesn't want to attempt to animate elements outside of the application
+          // therefore we need to ensure that the rootElement is an ancestor of the current element
+          rootElementDetected = isMatchingElement(parentElement, $rootElement);
+        }
+
+        if (parentElement.nodeType !== ELEMENT_NODE) {
+          // no point in inspecting the #document element
+          break;
+        }
+
+        var details = activeAnimationsLookup.get(parentElement) || {};
+        // either an enter, leave or move animation will commence
+        // therefore we can't allow any animations to take place
+        // but if a parent animation is class-based then that's ok
+        if (!parentAnimationDetected) {
+          var parentElementDisabled = disabledElementsLookup.get(parentElement);
+
+          if (parentElementDisabled === true && elementDisabled !== false) {
+            // disable animations if the user hasn't explicitly enabled animations on the
+            // current element
+            elementDisabled = true;
+            // element is disabled via parent element, no need to check anything else
+            break;
+          } else if (parentElementDisabled === false) {
+            elementDisabled = false;
+          }
+          parentAnimationDetected = details.structural;
+        }
+
+        if (isUndefined(animateChildren) || animateChildren === true) {
+          var value = jqLite.data(parentElement, NG_ANIMATE_CHILDREN_DATA);
+          if (isDefined(value)) {
+            animateChildren = value;
+          }
+        }
+
+        // there is no need to continue traversing at this point
+        if (parentAnimationDetected && animateChildren === false) break;
+
+        if (!bodyElementDetected) {
+          // we also need to ensure that the element is or will be a part of the body element
+          // otherwise it is pointless to even issue an animation to be rendered
+          bodyElementDetected = isMatchingElement(parentElement, bodyElement);
+        }
+
+        if (bodyElementDetected && rootElementDetected) {
+          // If both body and root have been found, any other checks are pointless,
+          // as no animation data should live outside the application
+          break;
+        }
+
+        if (!rootElementDetected) {
+          // If no rootElement is detected, check if the parentElement is pinned to another element
+          parentHost = jqLite.data(parentElement, NG_ANIMATE_PIN_DATA);
+          if (parentHost) {
+            // The pin target element becomes the next parent element
+            parentElement = getDomNode(parentHost);
+            continue;
+          }
+        }
+
+        parentElement = parentElement.parentNode;
+      }
+
+      var allowAnimation = (!parentAnimationDetected || animateChildren) && elementDisabled !== true;
+      return allowAnimation && rootElementDetected && bodyElementDetected;
+    }
+
+    function markElementAnimationState(element, state, details) {
+      details = details || {};
+      details.state = state;
+
+      var node = getDomNode(element);
+      node.setAttribute(NG_ANIMATE_ATTR_NAME, state);
+
+      var oldValue = activeAnimationsLookup.get(node);
+      var newValue = oldValue
+          ? extend(oldValue, details)
+          : details;
+      activeAnimationsLookup.put(node, newValue);
+    }
+  }];
+}];
+
+var $$AnimationProvider = ['$animateProvider', function($animateProvider) {
+  var NG_ANIMATE_REF_ATTR = 'ng-animate-ref';
+
+  var drivers = this.drivers = [];
+
+  var RUNNER_STORAGE_KEY = '$$animationRunner';
+
+  function setRunner(element, runner) {
+    element.data(RUNNER_STORAGE_KEY, runner);
+  }
+
+  function removeRunner(element) {
+    element.removeData(RUNNER_STORAGE_KEY);
+  }
+
+  function getRunner(element) {
+    return element.data(RUNNER_STORAGE_KEY);
+  }
+
+  this.$get = ['$$jqLite', '$rootScope', '$injector', '$$AnimateRunner', '$$HashMap', '$$rAFScheduler',
+       function($$jqLite,   $rootScope,   $injector,   $$AnimateRunner,   $$HashMap,   $$rAFScheduler) {
+
+    var animationQueue = [];
+    var applyAnimationClasses = applyAnimationClassesFactory($$jqLite);
+
+    function sortAnimations(animations) {
+      var tree = { children: [] };
+      var i, lookup = new $$HashMap();
+
+      // this is done first beforehand so that the hashmap
+      // is filled with a list of the elements that will be animated
+      for (i = 0; i < animations.length; i++) {
+        var animation = animations[i];
+        lookup.put(animation.domNode, animations[i] = {
+          domNode: animation.domNode,
+          fn: animation.fn,
+          children: []
+        });
+      }
+
+      for (i = 0; i < animations.length; i++) {
+        processNode(animations[i]);
+      }
+
+      return flatten(tree);
+
+      function processNode(entry) {
+        if (entry.processed) return entry;
+        entry.processed = true;
+
+        var elementNode = entry.domNode;
+        var parentNode = elementNode.parentNode;
+        lookup.put(elementNode, entry);
+
+        var parentEntry;
+        while (parentNode) {
+          parentEntry = lookup.get(parentNode);
+          if (parentEntry) {
+            if (!parentEntry.processed) {
+              parentEntry = processNode(parentEntry);
+            }
+            break;
+          }
+          parentNode = parentNode.parentNode;
+        }
+
+        (parentEntry || tree).children.push(entry);
+        return entry;
+      }
+
+      function flatten(tree) {
+        var result = [];
+        var queue = [];
+        var i;
+
+        for (i = 0; i < tree.children.length; i++) {
+          queue.push(tree.children[i]);
+        }
+
+        var remainingLevelEntries = queue.length;
+        var nextLevelEntries = 0;
+        var row = [];
+
+        for (i = 0; i < queue.length; i++) {
+          var entry = queue[i];
+          if (remainingLevelEntries <= 0) {
+            remainingLevelEntries = nextLevelEntries;
+            nextLevelEntries = 0;
+            result.push(row);
+            row = [];
+          }
+          row.push(entry.fn);
+          entry.children.forEach(function(childEntry) {
+            nextLevelEntries++;
+            queue.push(childEntry);
+          });
+          remainingLevelEntries--;
+        }
+
+        if (row.length) {
+          result.push(row);
+        }
+
+        return result;
+      }
+    }
+
+    // TODO(matsko): document the signature in a better way
+    return function(element, event, options) {
+      options = prepareAnimationOptions(options);
+      var isStructural = ['enter', 'move', 'leave'].indexOf(event) >= 0;
+
+      // there is no animation at the current moment, however
+      // these runner methods will get later updated with the
+      // methods leading into the driver's end/cancel methods
+      // for now they just stop the animation from starting
+      var runner = new $$AnimateRunner({
+        end: function() { close(); },
+        cancel: function() { close(true); }
+      });
+
+      if (!drivers.length) {
+        close();
+        return runner;
+      }
+
+      setRunner(element, runner);
+
+      var classes = mergeClasses(element.attr('class'), mergeClasses(options.addClass, options.removeClass));
+      var tempClasses = options.tempClasses;
+      if (tempClasses) {
+        classes += ' ' + tempClasses;
+        options.tempClasses = null;
+      }
+
+      var prepareClassName;
+      if (isStructural) {
+        prepareClassName = 'ng-' + event + PREPARE_CLASS_SUFFIX;
+        $$jqLite.addClass(element, prepareClassName);
+      }
+
+      animationQueue.push({
+        // this data is used by the postDigest code and passed into
+        // the driver step function
+        element: element,
+        classes: classes,
+        event: event,
+        structural: isStructural,
+        options: options,
+        beforeStart: beforeStart,
+        close: close
+      });
+
+      element.on('$destroy', handleDestroyedElement);
+
+      // we only want there to be one function called within the post digest
+      // block. This way we can group animations for all the animations that
+      // were apart of the same postDigest flush call.
+      if (animationQueue.length > 1) return runner;
+
+      $rootScope.$$postDigest(function() {
+        var animations = [];
+        forEach(animationQueue, function(entry) {
+          // the element was destroyed early on which removed the runner
+          // form its storage. This means we can't animate this element
+          // at all and it already has been closed due to destruction.
+          if (getRunner(entry.element)) {
+            animations.push(entry);
+          } else {
+            entry.close();
+          }
+        });
+
+        // now any future animations will be in another postDigest
+        animationQueue.length = 0;
+
+        var groupedAnimations = groupAnimations(animations);
+        var toBeSortedAnimations = [];
+
+        forEach(groupedAnimations, function(animationEntry) {
+          toBeSortedAnimations.push({
+            domNode: getDomNode(animationEntry.from ? animationEntry.from.element : animationEntry.element),
+            fn: function triggerAnimationStart() {
+              // it's important that we apply the `ng-animate` CSS class and the
+              // temporary classes before we do any driver invoking since these
+              // CSS classes may be required for proper CSS detection.
+              animationEntry.beforeStart();
+
+              var startAnimationFn, closeFn = animationEntry.close;
+
+              // in the event that the element was removed before the digest runs or
+              // during the RAF sequencing then we should not trigger the animation.
+              var targetElement = animationEntry.anchors
+                  ? (animationEntry.from.element || animationEntry.to.element)
+                  : animationEntry.element;
+
+              if (getRunner(targetElement)) {
+                var operation = invokeFirstDriver(animationEntry);
+                if (operation) {
+                  startAnimationFn = operation.start;
+                }
+              }
+
+              if (!startAnimationFn) {
+                closeFn();
+              } else {
+                var animationRunner = startAnimationFn();
+                animationRunner.done(function(status) {
+                  closeFn(!status);
+                });
+                updateAnimationRunners(animationEntry, animationRunner);
+              }
+            }
+          });
+        });
+
+        // we need to sort each of the animations in order of parent to child
+        // relationships. This ensures that the child classes are applied at the
+        // right time.
+        $$rAFScheduler(sortAnimations(toBeSortedAnimations));
+      });
+
+      return runner;
+
+      // TODO(matsko): change to reference nodes
+      function getAnchorNodes(node) {
+        var SELECTOR = '[' + NG_ANIMATE_REF_ATTR + ']';
+        var items = node.hasAttribute(NG_ANIMATE_REF_ATTR)
+              ? [node]
+              : node.querySelectorAll(SELECTOR);
+        var anchors = [];
+        forEach(items, function(node) {
+          var attr = node.getAttribute(NG_ANIMATE_REF_ATTR);
+          if (attr && attr.length) {
+            anchors.push(node);
+          }
+        });
+        return anchors;
+      }
+
+      function groupAnimations(animations) {
+        var preparedAnimations = [];
+        var refLookup = {};
+        forEach(animations, function(animation, index) {
+          var element = animation.element;
+          var node = getDomNode(element);
+          var event = animation.event;
+          var enterOrMove = ['enter', 'move'].indexOf(event) >= 0;
+          var anchorNodes = animation.structural ? getAnchorNodes(node) : [];
+
+          if (anchorNodes.length) {
+            var direction = enterOrMove ? 'to' : 'from';
+
+            forEach(anchorNodes, function(anchor) {
+              var key = anchor.getAttribute(NG_ANIMATE_REF_ATTR);
+              refLookup[key] = refLookup[key] || {};
+              refLookup[key][direction] = {
+                animationID: index,
+                element: jqLite(anchor)
+              };
+            });
+          } else {
+            preparedAnimations.push(animation);
+          }
+        });
+
+        var usedIndicesLookup = {};
+        var anchorGroups = {};
+        forEach(refLookup, function(operations, key) {
+          var from = operations.from;
+          var to = operations.to;
+
+          if (!from || !to) {
+            // only one of these is set therefore we can't have an
+            // anchor animation since all three pieces are required
+            var index = from ? from.animationID : to.animationID;
+            var indexKey = index.toString();
+            if (!usedIndicesLookup[indexKey]) {
+              usedIndicesLookup[indexKey] = true;
+              preparedAnimations.push(animations[index]);
+            }
+            return;
+          }
+
+          var fromAnimation = animations[from.animationID];
+          var toAnimation = animations[to.animationID];
+          var lookupKey = from.animationID.toString();
+          if (!anchorGroups[lookupKey]) {
+            var group = anchorGroups[lookupKey] = {
+              structural: true,
+              beforeStart: function() {
+                fromAnimation.beforeStart();
+                toAnimation.beforeStart();
+              },
+              close: function() {
+                fromAnimation.close();
+                toAnimation.close();
+              },
+              classes: cssClassesIntersection(fromAnimation.classes, toAnimation.classes),
+              from: fromAnimation,
+              to: toAnimation,
+              anchors: [] // TODO(matsko): change to reference nodes
+            };
+
+            // the anchor animations require that the from and to elements both have at least
+            // one shared CSS class which effectively marries the two elements together to use
+            // the same animation driver and to properly sequence the anchor animation.
+            if (group.classes.length) {
+              preparedAnimations.push(group);
+            } else {
+              preparedAnimations.push(fromAnimation);
+              preparedAnimations.push(toAnimation);
+            }
+          }
+
+          anchorGroups[lookupKey].anchors.push({
+            'out': from.element, 'in': to.element
+          });
+        });
+
+        return preparedAnimations;
+      }
+
+      function cssClassesIntersection(a,b) {
+        a = a.split(' ');
+        b = b.split(' ');
+        var matches = [];
+
+        for (var i = 0; i < a.length; i++) {
+          var aa = a[i];
+          if (aa.substring(0,3) === 'ng-') continue;
+
+          for (var j = 0; j < b.length; j++) {
+            if (aa === b[j]) {
+              matches.push(aa);
+              break;
+            }
+          }
+        }
+
+        return matches.join(' ');
+      }
+
+      function invokeFirstDriver(animationDetails) {
+        // we loop in reverse order since the more general drivers (like CSS and JS)
+        // may attempt more elements, but custom drivers are more particular
+        for (var i = drivers.length - 1; i >= 0; i--) {
+          var driverName = drivers[i];
+          var factory = $injector.get(driverName);
+          var driver = factory(animationDetails);
+          if (driver) {
+            return driver;
+          }
+        }
+      }
+
+      function beforeStart() {
+        element.addClass(NG_ANIMATE_CLASSNAME);
+        if (tempClasses) {
+          $$jqLite.addClass(element, tempClasses);
+        }
+        if (prepareClassName) {
+          $$jqLite.removeClass(element, prepareClassName);
+          prepareClassName = null;
+        }
+      }
+
+      function updateAnimationRunners(animation, newRunner) {
+        if (animation.from && animation.to) {
+          update(animation.from.element);
+          update(animation.to.element);
+        } else {
+          update(animation.element);
+        }
+
+        function update(element) {
+          var runner = getRunner(element);
+          if (runner) runner.setHost(newRunner);
+        }
+      }
+
+      function handleDestroyedElement() {
+        var runner = getRunner(element);
+        if (runner && (event !== 'leave' || !options.$$domOperationFired)) {
+          runner.end();
+        }
+      }
+
+      function close(rejected) { // jshint ignore:line
+        element.off('$destroy', handleDestroyedElement);
+        removeRunner(element);
+
+        applyAnimationClasses(element, options);
+        applyAnimationStyles(element, options);
+        options.domOperation();
+
+        if (tempClasses) {
+          $$jqLite.removeClass(element, tempClasses);
+        }
+
+        element.removeClass(NG_ANIMATE_CLASSNAME);
+        runner.complete(!rejected);
+      }
+    };
+  }];
+}];
+
+/**
+ * @ngdoc directive
+ * @name ngAnimateSwap
+ * @restrict A
+ * @scope
+ *
+ * @description
+ *
+ * ngAnimateSwap is a animation-oriented directive that allows for the container to
+ * be removed and entered in whenever the associated expression changes. A
+ * common usecase for this directive is a rotating banner or slider component which
+ * contains one image being present at a time. When the active image changes
+ * then the old image will perform a `leave` animation and the new element
+ * will be inserted via an `enter` animation.
+ *
+ * @animations
+ * | Animation                        | Occurs                               |
+ * |----------------------------------|--------------------------------------|
+ * | {@link ng.$animate#enter enter}  | when the new element is inserted to the DOM  |
+ * | {@link ng.$animate#leave leave}  | when the old element is removed from the DOM |
+ *
+ * @example
+ * <example name="ngAnimateSwap-directive" module="ngAnimateSwapExample"
+ *          deps="angular-animate.js"
+ *          animations="true" fixBase="true">
+ *   <file name="index.html">
+ *     <div class="container" ng-controller="AppCtrl">
+ *       <div ng-animate-swap="number" class="cell swap-animation" ng-class="colorClass(number)">
+ *         {{ number }}
+ *       </div>
+ *     </div>
+ *   </file>
+ *   <file name="script.js">
+ *     angular.module('ngAnimateSwapExample', ['ngAnimate'])
+ *       .controller('AppCtrl', ['$scope', '$interval', function($scope, $interval) {
+ *         $scope.number = 0;
+ *         $interval(function() {
+ *           $scope.number++;
+ *         }, 1000);
+ *
+ *         var colors = ['red','blue','green','yellow','orange'];
+ *         $scope.colorClass = function(number) {
+ *           return colors[number % colors.length];
+ *         };
+ *       }]);
+ *   </file>
+ *  <file name="animations.css">
+ *  .container {
+ *    height:250px;
+ *    width:250px;
+ *    position:relative;
+ *    overflow:hidden;
+ *    border:2px solid black;
+ *  }
+ *  .container .cell {
+ *    font-size:150px;
+ *    text-align:center;
+ *    line-height:250px;
+ *    position:absolute;
+ *    top:0;
+ *    left:0;
+ *    right:0;
+ *    border-bottom:2px solid black;
+ *  }
+ *  .swap-animation.ng-enter, .swap-animation.ng-leave {
+ *    transition:0.5s linear all;
+ *  }
+ *  .swap-animation.ng-enter {
+ *    top:-250px;
+ *  }
+ *  .swap-animation.ng-enter-active {
+ *    top:0px;
+ *  }
+ *  .swap-animation.ng-leave {
+ *    top:0px;
+ *  }
+ *  .swap-animation.ng-leave-active {
+ *    top:250px;
+ *  }
+ *  .red { background:red; }
+ *  .green { background:green; }
+ *  .blue { background:blue; }
+ *  .yellow { background:yellow; }
+ *  .orange { background:orange; }
+ *  </file>
+ * </example>
+ */
+var ngAnimateSwapDirective = ['$animate', '$rootScope', function($animate, $rootScope) {
+  return {
+    restrict: 'A',
+    transclude: 'element',
+    terminal: true,
+    priority: 600, // we use 600 here to ensure that the directive is caught before others
+    link: function(scope, $element, attrs, ctrl, $transclude) {
+      var previousElement, previousScope;
+      scope.$watchCollection(attrs.ngAnimateSwap || attrs['for'], function(value) {
+        if (previousElement) {
+          $animate.leave(previousElement);
+        }
+        if (previousScope) {
+          previousScope.$destroy();
+          previousScope = null;
+        }
+        if (value || value === 0) {
+          previousScope = scope.$new();
+          $transclude(previousScope, function(element) {
+            previousElement = element;
+            $animate.enter(element, null, $element);
+          });
+        }
+      });
+    }
+  };
+}];
+
+/**
+ * @ngdoc module
+ * @name ngAnimate
+ * @description
+ *
+ * The `ngAnimate` module provides support for CSS-based animations (keyframes and transitions) as well as JavaScript-based animations via
+ * callback hooks. Animations are not enabled by default, however, by including `ngAnimate` the animation hooks are enabled for an Angular app.
+ *
+ * <div doc-module-components="ngAnimate"></div>
+ *
+ * # Usage
+ * Simply put, there are two ways to make use of animations when ngAnimate is used: by using **CSS** and **JavaScript**. The former works purely based
+ * using CSS (by using matching CSS selectors/styles) and the latter triggers animations that are registered via `module.animation()`. For
+ * both CSS and JS animations the sole requirement is to have a matching `CSS class` that exists both in the registered animation and within
+ * the HTML element that the animation will be triggered on.
+ *
+ * ## Directive Support
+ * The following directives are "animation aware":
+ *
+ * | Directive                                                                                                | Supported Animations                                                     |
+ * |----------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------|
+ * | {@link ng.directive:ngRepeat#animations ngRepeat}                                                        | enter, leave and move                                                    |
+ * | {@link ngRoute.directive:ngView#animations ngView}                                                       | enter and leave                                                          |
+ * | {@link ng.directive:ngInclude#animations ngInclude}                                                      | enter and leave                                                          |
+ * | {@link ng.directive:ngSwitch#animations ngSwitch}                                                        | enter and leave                                                          |
+ * | {@link ng.directive:ngIf#animations ngIf}                                                                | enter and leave                                                          |
+ * | {@link ng.directive:ngClass#animations ngClass}                                                          | add and remove (the CSS class(es) present)                               |
+ * | {@link ng.directive:ngShow#animations ngShow} & {@link ng.directive:ngHide#animations ngHide}            | add and remove (the ng-hide class value)                                 |
+ * | {@link ng.directive:form#animation-hooks form} & {@link ng.directive:ngModel#animation-hooks ngModel}    | add and remove (dirty, pristine, valid, invalid & all other validations) |
+ * | {@link module:ngMessages#animations ngMessages}                                                          | add and remove (ng-active & ng-inactive)                                 |
+ * | {@link module:ngMessages#animations ngMessage}                                                           | enter and leave                                                          |
+ *
+ * (More information can be found by visiting each the documentation associated with each directive.)
+ *
+ * ## CSS-based Animations
+ *
+ * CSS-based animations with ngAnimate are unique since they require no JavaScript code at all. By using a CSS class that we reference between our HTML
+ * and CSS code we can create an animation that will be picked up by Angular when an the underlying directive performs an operation.
+ *
+ * The example below shows how an `enter` animation can be made possible on an element using `ng-if`:
+ *
+ * ```html
+ * <div ng-if="bool" class="fade">
+ *    Fade me in out
+ * </div>
+ * <button ng-click="bool=true">Fade In!</button>
+ * <button ng-click="bool=false">Fade Out!</button>
+ * ```
+ *
+ * Notice the CSS class **fade**? We can now create the CSS transition code that references this class:
+ *
+ * ```css
+ * /&#42; The starting CSS styles for the enter animation &#42;/
+ * .fade.ng-enter {
+ *   transition:0.5s linear all;
+ *   opacity:0;
+ * }
+ *
+ * /&#42; The finishing CSS styles for the enter animation &#42;/
+ * .fade.ng-enter.ng-enter-active {
+ *   opacity:1;
+ * }
+ * ```
+ *
+ * The key thing to remember here is that, depending on the animation event (which each of the directives above trigger depending on what's going on) two
+ * generated CSS classes will be applied to the element; in the example above we have `.ng-enter` and `.ng-enter-active`. For CSS transitions, the transition
+ * code **must** be defined within the starting CSS class (in this case `.ng-enter`). The destination class is what the transition will animate towards.
+ *
+ * If for example we wanted to create animations for `leave` and `move` (ngRepeat triggers move) then we can do so using the same CSS naming conventions:
+ *
+ * ```css
+ * /&#42; now the element will fade out before it is removed from the DOM &#42;/
+ * .fade.ng-leave {
+ *   transition:0.5s linear all;
+ *   opacity:1;
+ * }
+ * .fade.ng-leave.ng-leave-active {
+ *   opacity:0;
+ * }
+ * ```
+ *
+ * We can also make use of **CSS Keyframes** by referencing the keyframe animation within the starting CSS class:
+ *
+ * ```css
+ * /&#42; there is no need to define anything inside of the destination
+ * CSS class since the keyframe will take charge of the animation &#42;/
+ * .fade.ng-leave {
+ *   animation: my_fade_animation 0.5s linear;
+ *   -webkit-animation: my_fade_animation 0.5s linear;
+ * }
+ *
+ * @keyframes my_fade_animation {
+ *   from { opacity:1; }
+ *   to { opacity:0; }
+ * }
+ *
+ * @-webkit-keyframes my_fade_animation {
+ *   from { opacity:1; }
+ *   to { opacity:0; }
+ * }
+ * ```
+ *
+ * Feel free also mix transitions and keyframes together as well as any other CSS classes on the same element.
+ *
+ * ### CSS Class-based Animations
+ *
+ * Class-based animations (animations that are triggered via `ngClass`, `ngShow`, `ngHide` and some other directives) have a slightly different
+ * naming convention. Class-based animations are basic enough that a standard transition or keyframe can be referenced on the class being added
+ * and removed.
+ *
+ * For example if we wanted to do a CSS animation for `ngHide` then we place an animation on the `.ng-hide` CSS class:
+ *
+ * ```html
+ * <div ng-show="bool" class="fade">
+ *   Show and hide me
+ * </div>
+ * <button ng-click="bool=!bool">Toggle</button>
+ *
+ * <style>
+ * .fade.ng-hide {
+ *   transition:0.5s linear all;
+ *   opacity:0;
+ * }
+ * </style>
+ * ```
+ *
+ * All that is going on here with ngShow/ngHide behind the scenes is the `.ng-hide` class is added/removed (when the hidden state is valid). Since
+ * ngShow and ngHide are animation aware then we can match up a transition and ngAnimate handles the rest.
+ *
+ * In addition the addition and removal of the CSS class, ngAnimate also provides two helper methods that we can use to further decorate the animation
+ * with CSS styles.
+ *
+ * ```html
+ * <div ng-class="{on:onOff}" class="highlight">
+ *   Highlight this box
+ * </div>
+ * <button ng-click="onOff=!onOff">Toggle</button>
+ *
+ * <style>
+ * .highlight {
+ *   transition:0.5s linear all;
+ * }
+ * .highlight.on-add {
+ *   background:white;
+ * }
+ * .highlight.on {
+ *   background:yellow;
+ * }
+ * .highlight.on-remove {
+ *   background:black;
+ * }
+ * </style>
+ * ```
+ *
+ * We can also make use of CSS keyframes by placing them within the CSS classes.
+ *
+ *
+ * ### CSS Staggering Animations
+ * A Staggering animation is a collection of animations that are issued with a slight delay in between each successive operation resulting in a
+ * curtain-like effect. The ngAnimate module (versions >=1.2) supports staggering animations and the stagger effect can be
+ * performed by creating a **ng-EVENT-stagger** CSS class and attaching that class to the base CSS class used for
+ * the animation. The style property expected within the stagger class can either be a **transition-delay** or an
+ * **animation-delay** property (or both if your animation contains both transitions and keyframe animations).
+ *
+ * ```css
+ * .my-animation.ng-enter {
+ *   /&#42; standard transition code &#42;/
+ *   transition: 1s linear all;
+ *   opacity:0;
+ * }
+ * .my-animation.ng-enter-stagger {
+ *   /&#42; this will have a 100ms delay between each successive leave animation &#42;/
+ *   transition-delay: 0.1s;
+ *
+ *   /&#42; As of 1.4.4, this must always be set: it signals ngAnimate
+ *     to not accidentally inherit a delay property from another CSS class &#42;/
+ *   transition-duration: 0s;
+ * }
+ * .my-animation.ng-enter.ng-enter-active {
+ *   /&#42; standard transition styles &#42;/
+ *   opacity:1;
+ * }
+ * ```
+ *
+ * Staggering animations work by default in ngRepeat (so long as the CSS class is defined). Outside of ngRepeat, to use staggering animations
+ * on your own, they can be triggered by firing multiple calls to the same event on $animate. However, the restrictions surrounding this
+ * are that each of the elements must have the same CSS className value as well as the same parent element. A stagger operation
+ * will also be reset if one or more animation frames have passed since the multiple calls to `$animate` were fired.
+ *
+ * The following code will issue the **ng-leave-stagger** event on the element provided:
+ *
+ * ```js
+ * var kids = parent.children();
+ *
+ * $animate.leave(kids[0]); //stagger index=0
+ * $animate.leave(kids[1]); //stagger index=1
+ * $animate.leave(kids[2]); //stagger index=2
+ * $animate.leave(kids[3]); //stagger index=3
+ * $animate.leave(kids[4]); //stagger index=4
+ *
+ * window.requestAnimationFrame(function() {
+ *   //stagger has reset itself
+ *   $animate.leave(kids[5]); //stagger index=0
+ *   $animate.leave(kids[6]); //stagger index=1
+ *
+ *   $scope.$digest();
+ * });
+ * ```
+ *
+ * Stagger animations are currently only supported within CSS-defined animations.
+ *
+ * ### The `ng-animate` CSS class
+ *
+ * When ngAnimate is animating an element it will apply the `ng-animate` CSS class to the element for the duration of the animation.
+ * This is a temporary CSS class and it will be removed once the animation is over (for both JavaScript and CSS-based animations).
+ *
+ * Therefore, animations can be applied to an element using this temporary class directly via CSS.
+ *
+ * ```css
+ * .zipper.ng-animate {
+ *   transition:0.5s linear all;
+ * }
+ * .zipper.ng-enter {
+ *   opacity:0;
+ * }
+ * .zipper.ng-enter.ng-enter-active {
+ *   opacity:1;
+ * }
+ * .zipper.ng-leave {
+ *   opacity:1;
+ * }
+ * .zipper.ng-leave.ng-leave-active {
+ *   opacity:0;
+ * }
+ * ```
+ *
+ * (Note that the `ng-animate` CSS class is reserved and it cannot be applied on an element directly since ngAnimate will always remove
+ * the CSS class once an animation has completed.)
+ *
+ *
+ * ### The `ng-[event]-prepare` class
+ *
+ * This is a special class that can be used to prevent unwanted flickering / flash of content before
+ * the actual animation starts. The class is added as soon as an animation is initialized, but removed
+ * before the actual animation starts (after waiting for a $digest).
+ * It is also only added for *structural* animations (`enter`, `move`, and `leave`).
+ *
+ * In practice, flickering can appear when nesting elements with structural animations such as `ngIf`
+ * into elements that have class-based animations such as `ngClass`.
+ *
+ * ```html
+ * <div ng-class="{red: myProp}">
+ *   <div ng-class="{blue: myProp}">
+ *     <div class="message" ng-if="myProp"></div>
+ *   </div>
+ * </div>
+ * ```
+ *
+ * It is possible that during the `enter` animation, the `.message` div will be briefly visible before it starts animating.
+ * In that case, you can add styles to the CSS that make sure the element stays hidden before the animation starts:
+ *
+ * ```css
+ * .message.ng-enter-prepare {
+ *   opacity: 0;
+ * }
+ *
+ * ```
+ *
+ * ## JavaScript-based Animations
+ *
+ * ngAnimate also allows for animations to be consumed by JavaScript code. The approach is similar to CSS-based animations (where there is a shared
+ * CSS class that is referenced in our HTML code) but in addition we need to register the JavaScript animation on the module. By making use of the
+ * `module.animation()` module function we can register the animation.
+ *
+ * Let's see an example of a enter/leave animation using `ngRepeat`:
+ *
+ * ```html
+ * <div ng-repeat="item in items" class="slide">
+ *   {{ item }}
+ * </div>
+ * ```
+ *
+ * See the **slide** CSS class? Let's use that class to define an animation that we'll structure in our module code by using `module.animation`:
+ *
+ * ```js
+ * myModule.animation('.slide', [function() {
+ *   return {
+ *     // make note that other events (like addClass/removeClass)
+ *     // have different function input parameters
+ *     enter: function(element, doneFn) {
+ *       jQuery(element).fadeIn(1000, doneFn);
+ *
+ *       // remember to call doneFn so that angular
+ *       // knows that the animation has concluded
+ *     },
+ *
+ *     move: function(element, doneFn) {
+ *       jQuery(element).fadeIn(1000, doneFn);
+ *     },
+ *
+ *     leave: function(element, doneFn) {
+ *       jQuery(element).fadeOut(1000, doneFn);
+ *     }
+ *   }
+ * }]);
+ * ```
+ *
+ * The nice thing about JS-based animations is that we can inject other services and make use of advanced animation libraries such as
+ * greensock.js and velocity.js.
+ *
+ * If our animation code class-based (meaning that something like `ngClass`, `ngHide` and `ngShow` triggers it) then we can still define
+ * our animations inside of the same registered animation, however, the function input arguments are a bit different:
+ *
+ * ```html
+ * <div ng-class="color" class="colorful">
+ *   this box is moody
+ * </div>
+ * <button ng-click="color='red'">Change to red</button>
+ * <button ng-click="color='blue'">Change to blue</button>
+ * <button ng-click="color='green'">Change to green</button>
+ * ```
+ *
+ * ```js
+ * myModule.animation('.colorful', [function() {
+ *   return {
+ *     addClass: function(element, className, doneFn) {
+ *       // do some cool animation and call the doneFn
+ *     },
+ *     removeClass: function(element, className, doneFn) {
+ *       // do some cool animation and call the doneFn
+ *     },
+ *     setClass: function(element, addedClass, removedClass, doneFn) {
+ *       // do some cool animation and call the doneFn
+ *     }
+ *   }
+ * }]);
+ * ```
+ *
+ * ## CSS + JS Animations Together
+ *
+ * AngularJS 1.4 and higher has taken steps to make the amalgamation of CSS and JS animations more flexible. However, unlike earlier versions of Angular,
+ * defining CSS and JS animations to work off of the same CSS class will not work anymore. Therefore the example below will only result in **JS animations taking
+ * charge of the animation**:
+ *
+ * ```html
+ * <div ng-if="bool" class="slide">
+ *   Slide in and out
+ * </div>
+ * ```
+ *
+ * ```js
+ * myModule.animation('.slide', [function() {
+ *   return {
+ *     enter: function(element, doneFn) {
+ *       jQuery(element).slideIn(1000, doneFn);
+ *     }
+ *   }
+ * }]);
+ * ```
+ *
+ * ```css
+ * .slide.ng-enter {
+ *   transition:0.5s linear all;
+ *   transform:translateY(-100px);
+ * }
+ * .slide.ng-enter.ng-enter-active {
+ *   transform:translateY(0);
+ * }
+ * ```
+ *
+ * Does this mean that CSS and JS animations cannot be used together? Do JS-based animations always have higher priority? We can make up for the
+ * lack of CSS animations by using the `$animateCss` service to trigger our own tweaked-out, CSS-based animations directly from
+ * our own JS-based animation code:
+ *
+ * ```js
+ * myModule.animation('.slide', ['$animateCss', function($animateCss) {
+ *   return {
+ *     enter: function(element) {
+*        // this will trigger `.slide.ng-enter` and `.slide.ng-enter-active`.
+ *       return $animateCss(element, {
+ *         event: 'enter',
+ *         structural: true
+ *       });
+ *     }
+ *   }
+ * }]);
+ * ```
+ *
+ * The nice thing here is that we can save bandwidth by sticking to our CSS-based animation code and we don't need to rely on a 3rd-party animation framework.
+ *
+ * The `$animateCss` service is very powerful since we can feed in all kinds of extra properties that will be evaluated and fed into a CSS transition or
+ * keyframe animation. For example if we wanted to animate the height of an element while adding and removing classes then we can do so by providing that
+ * data into `$animateCss` directly:
+ *
+ * ```js
+ * myModule.animation('.slide', ['$animateCss', function($animateCss) {
+ *   return {
+ *     enter: function(element) {
+ *       return $animateCss(element, {
+ *         event: 'enter',
+ *         structural: true,
+ *         addClass: 'maroon-setting',
+ *         from: { height:0 },
+ *         to: { height: 200 }
+ *       });
+ *     }
+ *   }
+ * }]);
+ * ```
+ *
+ * Now we can fill in the rest via our transition CSS code:
+ *
+ * ```css
+ * /&#42; the transition tells ngAnimate to make the animation happen &#42;/
+ * .slide.ng-enter { transition:0.5s linear all; }
+ *
+ * /&#42; this extra CSS class will be absorbed into the transition
+ * since the $animateCss code is adding the class &#42;/
+ * .maroon-setting { background:red; }
+ * ```
+ *
+ * And `$animateCss` will figure out the rest. Just make sure to have the `done()` callback fire the `doneFn` function to signal when the animation is over.
+ *
+ * To learn more about what's possible be sure to visit the {@link ngAnimate.$animateCss $animateCss service}.
+ *
+ * ## Animation Anchoring (via `ng-animate-ref`)
+ *
+ * ngAnimate in AngularJS 1.4 comes packed with the ability to cross-animate elements between
+ * structural areas of an application (like views) by pairing up elements using an attribute
+ * called `ng-animate-ref`.
+ *
+ * Let's say for example we have two views that are managed by `ng-view` and we want to show
+ * that there is a relationship between two components situated in within these views. By using the
+ * `ng-animate-ref` attribute we can identify that the two components are paired together and we
+ * can then attach an animation, which is triggered when the view changes.
+ *
+ * Say for example we have the following template code:
+ *
+ * ```html
+ * <!-- index.html -->
+ * <div ng-view class="view-animation">
+ * </div>
+ *
+ * <!-- home.html -->
+ * <a href="#/banner-page">
+ *   <img src="./banner.jpg" class="banner" ng-animate-ref="banner">
+ * </a>
+ *
+ * <!-- banner-page.html -->
+ * <img src="./banner.jpg" class="banner" ng-animate-ref="banner">
+ * ```
+ *
+ * Now, when the view changes (once the link is clicked), ngAnimate will examine the
+ * HTML contents to see if there is a match reference between any components in the view
+ * that is leaving and the view that is entering. It will scan both the view which is being
+ * removed (leave) and inserted (enter) to see if there are any paired DOM elements that
+ * contain a matching ref value.
+ *
+ * The two images match since they share the same ref value. ngAnimate will now create a
+ * transport element (which is a clone of the first image element) and it will then attempt
+ * to animate to the position of the second image element in the next view. For the animation to
+ * work a special CSS class called `ng-anchor` will be added to the transported element.
+ *
+ * We can now attach a transition onto the `.banner.ng-anchor` CSS class and then
+ * ngAnimate will handle the entire transition for us as well as the addition and removal of
+ * any changes of CSS classes between the elements:
+ *
+ * ```css
+ * .banner.ng-anchor {
+ *   /&#42; this animation will last for 1 second since there are
+ *          two phases to the animation (an `in` and an `out` phase) &#42;/
+ *   transition:0.5s linear all;
+ * }
+ * ```
+ *
+ * We also **must** include animations for the views that are being entered and removed
+ * (otherwise anchoring wouldn't be possible since the new view would be inserted right away).
+ *
+ * ```css
+ * .view-animation.ng-enter, .view-animation.ng-leave {
+ *   transition:0.5s linear all;
+ *   position:fixed;
+ *   left:0;
+ *   top:0;
+ *   width:100%;
+ * }
+ * .view-animation.ng-enter {
+ *   transform:translateX(100%);
+ * }
+ * .view-animation.ng-leave,
+ * .view-animation.ng-enter.ng-enter-active {
+ *   transform:translateX(0%);
+ * }
+ * .view-animation.ng-leave.ng-leave-active {
+ *   transform:translateX(-100%);
+ * }
+ * ```
+ *
+ * Now we can jump back to the anchor animation. When the animation happens, there are two stages that occur:
+ * an `out` and an `in` stage. The `out` stage happens first and that is when the element is animated away
+ * from its origin. Once that animation is over then the `in` stage occurs which animates the
+ * element to its destination. The reason why there are two animations is to give enough time
+ * for the enter animation on the new element to be ready.
+ *
+ * The example above sets up a transition for both the in and out phases, but we can also target the out or
+ * in phases directly via `ng-anchor-out` and `ng-anchor-in`.
+ *
+ * ```css
+ * .banner.ng-anchor-out {
+ *   transition: 0.5s linear all;
+ *
+ *   /&#42; the scale will be applied during the out animation,
+ *          but will be animated away when the in animation runs &#42;/
+ *   transform: scale(1.2);
+ * }
+ *
+ * .banner.ng-anchor-in {
+ *   transition: 1s linear all;
+ * }
+ * ```
+ *
+ *
+ *
+ *
+ * ### Anchoring Demo
+ *
+  <example module="anchoringExample"
+           name="anchoringExample"
+           id="anchoringExample"
+           deps="angular-animate.js;angular-route.js"
+           animations="true">
+    <file name="index.html">
+      <a href="#/">Home</a>
+      <hr />
+      <div class="view-container">
+        <div ng-view class="view"></div>
+      </div>
+    </file>
+    <file name="script.js">
+      angular.module('anchoringExample', ['ngAnimate', 'ngRoute'])
+        .config(['$routeProvider', function($routeProvider) {
+          $routeProvider.when('/', {
+            templateUrl: 'home.html',
+            controller: 'HomeController as home'
+          });
+          $routeProvider.when('/profile/:id', {
+            templateUrl: 'profile.html',
+            controller: 'ProfileController as profile'
+          });
+        }])
+        .run(['$rootScope', function($rootScope) {
+          $rootScope.records = [
+            { id:1, title: "Miss Beulah Roob" },
+            { id:2, title: "Trent Morissette" },
+            { id:3, title: "Miss Ava Pouros" },
+            { id:4, title: "Rod Pouros" },
+            { id:5, title: "Abdul Rice" },
+            { id:6, title: "Laurie Rutherford Sr." },
+            { id:7, title: "Nakia McLaughlin" },
+            { id:8, title: "Jordon Blanda DVM" },
+            { id:9, title: "Rhoda Hand" },
+            { id:10, title: "Alexandrea Sauer" }
+          ];
+        }])
+        .controller('HomeController', [function() {
+          //empty
+        }])
+        .controller('ProfileController', ['$rootScope', '$routeParams', function($rootScope, $routeParams) {
+          var index = parseInt($routeParams.id, 10);
+          var record = $rootScope.records[index - 1];
+
+          this.title = record.title;
+          this.id = record.id;
+        }]);
+    </file>
+    <file name="home.html">
+      <h2>Welcome to the home page</h1>
+      <p>Please click on an element</p>
+      <a class="record"
+         ng-href="#/profile/{{ record.id }}"
+         ng-animate-ref="{{ record.id }}"
+         ng-repeat="record in records">
+        {{ record.title }}
+      </a>
+    </file>
+    <file name="profile.html">
+      <div class="profile record" ng-animate-ref="{{ profile.id }}">
+        {{ profile.title }}
+      </div>
+    </file>
+    <file name="animations.css">
+      .record {
+        display:block;
+        font-size:20px;
+      }
+      .profile {
+        background:black;
+        color:white;
+        font-size:100px;
+      }
+      .view-container {
+        position:relative;
+      }
+      .view-container > .view.ng-animate {
+        position:absolute;
+        top:0;
+        left:0;
+        width:100%;
+        min-height:500px;
+      }
+      .view.ng-enter, .view.ng-leave,
+      .record.ng-anchor {
+        transition:0.5s linear all;
+      }
+      .view.ng-enter {
+        transform:translateX(100%);
+      }
+      .view.ng-enter.ng-enter-active, .view.ng-leave {
+        transform:translateX(0%);
+      }
+      .view.ng-leave.ng-leave-active {
+        transform:translateX(-100%);
+      }
+      .record.ng-anchor-out {
+        background:red;
+      }
+    </file>
+  </example>
+ *
+ * ### How is the element transported?
+ *
+ * When an anchor animation occurs, ngAnimate will clone the starting element and position it exactly where the starting
+ * element is located on screen via absolute positioning. The cloned element will be placed inside of the root element
+ * of the application (where ng-app was defined) and all of the CSS classes of the starting element will be applied. The
+ * element will then animate into the `out` and `in` animations and will eventually reach the coordinates and match
+ * the dimensions of the destination element. During the entire animation a CSS class of `.ng-animate-shim` will be applied
+ * to both the starting and destination elements in order to hide them from being visible (the CSS styling for the class
+ * is: `visibility:hidden`). Once the anchor reaches its destination then it will be removed and the destination element
+ * will become visible since the shim class will be removed.
+ *
+ * ### How is the morphing handled?
+ *
+ * CSS Anchoring relies on transitions and keyframes and the internal code is intelligent enough to figure out
+ * what CSS classes differ between the starting element and the destination element. These different CSS classes
+ * will be added/removed on the anchor element and a transition will be applied (the transition that is provided
+ * in the anchor class). Long story short, ngAnimate will figure out what classes to add and remove which will
+ * make the transition of the element as smooth and automatic as possible. Be sure to use simple CSS classes that
+ * do not rely on DOM nesting structure so that the anchor element appears the same as the starting element (since
+ * the cloned element is placed inside of root element which is likely close to the body element).
+ *
+ * Note that if the root element is on the `<html>` element then the cloned node will be placed inside of body.
+ *
+ *
+ * ## Using $animate in your directive code
+ *
+ * So far we've explored how to feed in animations into an Angular application, but how do we trigger animations within our own directives in our application?
+ * By injecting the `$animate` service into our directive code, we can trigger structural and class-based hooks which can then be consumed by animations. Let's
+ * imagine we have a greeting box that shows and hides itself when the data changes
+ *
+ * ```html
+ * <greeting-box active="onOrOff">Hi there</greeting-box>
+ * ```
+ *
+ * ```js
+ * ngModule.directive('greetingBox', ['$animate', function($animate) {
+ *   return function(scope, element, attrs) {
+ *     attrs.$observe('active', function(value) {
+ *       value ? $animate.addClass(element, 'on') : $animate.removeClass(element, 'on');
+ *     });
+ *   });
+ * }]);
+ * ```
+ *
+ * Now the `on` CSS class is added and removed on the greeting box component. Now if we add a CSS class on top of the greeting box element
+ * in our HTML code then we can trigger a CSS or JS animation to happen.
+ *
+ * ```css
+ * /&#42; normally we would create a CSS class to reference on the element &#42;/
+ * greeting-box.on { transition:0.5s linear all; background:green; color:white; }
+ * ```
+ *
+ * The `$animate` service contains a variety of other methods like `enter`, `leave`, `animate` and `setClass`. To learn more about what's
+ * possible be sure to visit the {@link ng.$animate $animate service API page}.
+ *
+ *
+ * ## Callbacks and Promises
+ *
+ * When `$animate` is called it returns a promise that can be used to capture when the animation has ended. Therefore if we were to trigger
+ * an animation (within our directive code) then we can continue performing directive and scope related activities after the animation has
+ * ended by chaining onto the returned promise that animation method returns.
+ *
+ * ```js
+ * // somewhere within the depths of the directive
+ * $animate.enter(element, parent).then(function() {
+ *   //the animation has completed
+ * });
+ * ```
+ *
+ * (Note that earlier versions of Angular prior to v1.4 required the promise code to be wrapped using `$scope.$apply(...)`. This is not the case
+ * anymore.)
+ *
+ * In addition to the animation promise, we can also make use of animation-related callbacks within our directives and controller code by registering
+ * an event listener using the `$animate` service. Let's say for example that an animation was triggered on our view
+ * routing controller to hook into that:
+ *
+ * ```js
+ * ngModule.controller('HomePageController', ['$animate', function($animate) {
+ *   $animate.on('enter', ngViewElement, function(element) {
+ *     // the animation for this route has completed
+ *   }]);
+ * }])
+ * ```
+ *
+ * (Note that you will need to trigger a digest within the callback to get angular to notice any scope-related changes.)
+ */
+
+var copy;
+var extend;
+var forEach;
+var isArray;
+var isDefined;
+var isElement;
+var isFunction;
+var isObject;
+var isString;
+var isUndefined;
+var jqLite;
+var noop;
+
+/**
+ * @ngdoc service
+ * @name $animate
+ * @kind object
+ *
+ * @description
+ * The ngAnimate `$animate` service documentation is the same for the core `$animate` service.
+ *
+ * Click here {@link ng.$animate to learn more about animations with `$animate`}.
+ */
+angular.module('ngAnimate', [], function initAngularHelpers() {
+  // Access helpers from angular core.
+  // Do it inside a `config` block to ensure `window.angular` is available.
+  noop        = angular.noop;
+  copy        = angular.copy;
+  extend      = angular.extend;
+  jqLite      = angular.element;
+  forEach     = angular.forEach;
+  isArray     = angular.isArray;
+  isString    = angular.isString;
+  isObject    = angular.isObject;
+  isUndefined = angular.isUndefined;
+  isDefined   = angular.isDefined;
+  isFunction  = angular.isFunction;
+  isElement   = angular.isElement;
+})
+  .directive('ngAnimateSwap', ngAnimateSwapDirective)
+
+  .directive('ngAnimateChildren', $$AnimateChildrenDirective)
+  .factory('$$rAFScheduler', $$rAFSchedulerFactory)
+
+  .provider('$$animateQueue', $$AnimateQueueProvider)
+  .provider('$$animation', $$AnimationProvider)
+
+  .provider('$animateCss', $AnimateCssProvider)
+  .provider('$$animateCssDriver', $$AnimateCssDriverProvider)
+
+  .provider('$$animateJs', $$AnimateJsProvider)
+  .provider('$$animateJsDriver', $$AnimateJsDriverProvider);
+
+
+})(window, window.angular);