Refactoring the way begin frame sources inside scheduler work.

cc/test/begin_frame_args_test.h

Index: cc/test/begin_frame_args_test.h
diff --git a/cc/test/begin_frame_args_test.h b/cc/test/begin_frame_args_test.h
index 1c75c3775f5845b6ed2c0eae1bb8f0bd6bcb819b..425a07b7f07a25dde2c0ba0f7ed4af274b6fa6bb 100644
--- a/cc/test/begin_frame_args_test.h
+++ b/cc/test/begin_frame_args_test.h
@@ -20,6 +20,11 @@ BeginFrameArgs CreateBeginFrameArgsForTesting(base::TimeTicks frame_time);
 BeginFrameArgs CreateBeginFrameArgsForTesting(int64 frame_time,
                                               int64 deadline,
                                               int64 interval);
+BeginFrameArgs CreateTypedBeginFrameArgsForTesting(
+    int64 frame_time,
+    int64 deadline,
+    int64 interval,
+    BeginFrameArgs::BeginFrameArgsType type);
 BeginFrameArgs CreateExpiredBeginFrameArgsForTesting();
 
 // Creates a BeginFrameArgs using the fake Now value stored on the