cc: Emulate BeginFrame in OutputSurfaces that don't support it natively

cc/scheduler/frame_rate_controller.h

Index: cc/scheduler/frame_rate_controller.h
diff --git a/cc/scheduler/frame_rate_controller.h b/cc/scheduler/frame_rate_controller.h
index 9210a670d9992523c055a35e16310fcddbc6318b..5f8f5c8e81158cafa87ec85f76549cfbd9c81019 100644
--- a/cc/scheduler/frame_rate_controller.h
+++ b/cc/scheduler/frame_rate_controller.h
@@ -15,18 +15,21 @@ namespace cc {
 
 class Thread;
 class TimeSource;
+class FrameRateController;
 
 class CC_EXPORT FrameRateControllerClient {
- public:
-  // Throttled is true when we have a maximum number of frames pending.
-  virtual void BeginFrame(bool throttled) = 0;
-
  protected:
   virtual ~FrameRateControllerClient() {}
+
+ public:
+  // Throttled is true when we have a maximum number of frames pending.
+  virtual void FrameRateControllerTick(bool throttled) = 0;
 };
 
 class FrameRateControllerTimeSourceAdapter;
 
+// The FrameRateController is used in cases where we self-tick (i.e. BeginFrame
+// is not sent by a parent compositor.
 class CC_EXPORT FrameRateController {
  public:
   enum {
@@ -48,7 +51,7 @@ class CC_EXPORT FrameRateController {
   // DidFinishFrame should be posted.
   //
   // If the rendering pipeline crashes, call DidAbortAllPendingFrames.
-  void DidSwapBuffers();
+  void WillSwapBuffers();
   void DidSwapBuffersComplete();
   void DidAbortAllPendingFrames();
   void SetMaxFramesPending(int max_frames_pending);  // 0 for unlimited.