dbus: transition to interface for testing

To make testing easier, the dbus objects now receive a
helper interface to use instead of calling into a helper module.

Tested: Ran on quanta-q71l board and it behaved as expected.

Change-Id: I2521d9c75aec76e92d2e26dc044d01011e44d552
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/dbus/util.cpp b/dbus/util.cpp
index 7e1f9a5..f0ffffb 100644
--- a/dbus/util.cpp
+++ b/dbus/util.cpp
@@ -9,9 +9,9 @@
 /* TODO(venture): Basically all phosphor apps need this, maybe it should be a
  * part of sdbusplus.  There is an old version in libmapper.
  */
-std::string GetService(sdbusplus::bus::bus& bus,
-                       const std::string& intf,
-                       const std::string& path)
+std::string DbusHelper::GetService(sdbusplus::bus::bus& bus,
+                                   const std::string& intf,
+                                   const std::string& path)
 {
     auto mapper = bus.new_method_call(
                       "xyz.openbmc_project.ObjectMapper",
@@ -39,12 +39,11 @@
     return response.begin()->first;
 }
 
-void GetProperties(sdbusplus::bus::bus& bus,
-                   const std::string& service,
-                   const std::string& path,
-                   struct SensorProperties* prop)
+void DbusHelper::GetProperties(sdbusplus::bus::bus& bus,
+                               const std::string& service,
+                               const std::string& path,
+                               struct SensorProperties* prop)
 {
-
     auto pimMsg = bus.new_method_call(service.c_str(),
                                       path.c_str(),
                                       propertiesintf.c_str(),
@@ -69,9 +68,12 @@
     valueResponseMsg.read(propMap);
 
     // If no error was set, the values should all be there.
-    prop->unit = sdbusplus::message::variant_ns::get<std::string>(propMap["Unit"]);
-    prop->scale = sdbusplus::message::variant_ns::get<int64_t>(propMap["Scale"]);
-    prop->value = sdbusplus::message::variant_ns::get<int64_t>(propMap["Value"]);
+    prop->unit = sdbusplus::message::variant_ns::get<std::string>(
+        propMap["Unit"]);
+    prop->scale = sdbusplus::message::variant_ns::get<int64_t>(
+        propMap["Scale"]);
+    prop->value = sdbusplus::message::variant_ns::get<int64_t>(
+        propMap["Value"]);
 
     return;
 }