cc: Make scheduling be driven by vsync for android webview.

content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.h

Index: content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.h
diff --git a/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.h b/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.h
index dd62360f7ca713bd7d9bc9fdf2b721bf1328d048..d5aedf97d403ce8957eace880462ad1356f79f49 100644
--- a/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.h
+++ b/content/browser/android/in_process/synchronous_compositor_external_begin_frame_source.h
@@ -20,10 +20,15 @@ class SynchronousCompositorExternalBeginFrameSource
   explicit SynchronousCompositorExternalBeginFrameSource(int routing_id);
   virtual ~SynchronousCompositorExternalBeginFrameSource();
 
-  void BeginFrame();
+  bool InsideBeginFrame() const { return inside_begin_frame_; }
+  void SendBeginFrameNow(); // Uses cc::BeginFrameArgs::DefaultInterval.

[brianderson, 2014/12/20 00:34:13]

Why do you need this?

[sunnyps, 2014/12/20 00:39:30]

This is for out-of-sequence draws on Android. For e.g. when onDraw is called by
user code.

E.g. someone might have a webview that's not attached to the view hierarchy but
it's still being used to draw at regular intervals to a canvas.

+  void SendBeginFrame(base::TimeTicks frame_time, base::TimeDelta vsync_period);
 
   void SetCompositor(SynchronousCompositorImpl* compositor);
 
+  // cc::BeginFrameSource implementation.
+  void DidFinishFrame(size_t remaining_frames) override;
+
   // cc::BeginFrameSourceMixIn implementation.
   void OnNeedsBeginFramesChange(bool needs_begin_frames) override;
   void SetClientReady() override;
@@ -33,6 +38,7 @@ class SynchronousCompositorExternalBeginFrameSource
 
   const int routing_id_;
   bool registered_;
+  bool inside_begin_frame_;
 
   // Not owned. This can be null when compositor is gone first than BFS.
   SynchronousCompositorImpl* compositor_;