clang-format-6.0 bump fixes

The bump to use clang-format-6.0 now reports these issues.

Change-Id: I174c882727eaa9adf472599443a2f8ef637e2f0a
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/src/test/propertywatchtest.cpp b/src/test/propertywatchtest.cpp
index 6576bfd..bb021a2 100644
--- a/src/test/propertywatchtest.cpp
+++ b/src/test/propertywatchtest.cpp
@@ -107,8 +107,8 @@
 
 template <typename T> void testStart()
 {
-    using ::testing::Return;
     using ::testing::_;
+    using ::testing::Return;
 
     MockDBusInterface dbus;
     MockDBusInterface::instance(dbus);