cc: Implement unified BeginFrame on aura

cc/output/begin_frame_args.h

Index: cc/output/begin_frame_args.h
diff --git a/cc/output/begin_frame_args.h b/cc/output/begin_frame_args.h
index ba29523983bfddd259404667e979035e26ea247a..7e665241a929f5bb6d1ee44a7c86e09344c3ecf1 100644
--- a/cc/output/begin_frame_args.h
+++ b/cc/output/begin_frame_args.h
@@ -83,6 +83,15 @@ struct CC_EXPORT BeginFrameArgs {
   scoped_refptr<base::debug::ConvertableToTraceFormat> AsValue() const;
   void AsValueInto(base::debug::TracedValue* dict) const;
 
+  bool operator==(const BeginFrameArgs& other) const {
+    return (frame_time == other.frame_time && deadline == other.deadline &&
+            interval == other.interval && type == other.type);
+  }
+  bool operator!=(const BeginFrameArgs& other) const {
+    return (frame_time != other.frame_time || deadline != other.deadline ||
+            interval != other.interval || type != other.type);
+  }
+
   base::TimeTicks frame_time;
   base::TimeTicks deadline;
   base::TimeDelta interval;