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

cc/trees/layer_tree_host_impl.h

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_TREES_LAYER_TREE_HOST_IMPL_H_
 #define CC_TREES_LAYER_TREE_HOST_IMPL_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 102 matching lines @@
   virtual bool IsInsideDraw() = 0;
   virtual void RenewTreePriority() = 0;
   virtual void PostDelayedAnimationTaskOnImplThread(const base::Closure& task,
                                                     base::TimeDelta delay) = 0;
   virtual void DidActivateSyncTree() = 0;
   virtual void DidPrepareTiles() = 0;
 
   // Called when page scale animation has completed on the impl thread.
   virtual void DidCompletePageScaleAnimationOnImplThread() = 0;
 
+  // Called when output surface asks for a draw.
+  virtual void OnDrawForOutputSurface() = 0;
+
  protected:
   virtual ~LayerTreeHostImplClient() {}
 };
 
 // LayerTreeHostImpl owns the LayerImpl trees as well as associated rendering
 // state.
 class CC_EXPORT LayerTreeHostImpl
     : public InputHandler,
       public RendererClient,
       public TileManagerClient,
@@ skipping 154 matching lines @@
       const gfx::Rect& clip,
       const gfx::Rect& viewport_rect_for_tile_priority,
       const gfx::Transform& transform_for_tile_priority,
       bool resourceless_software_draw) override;
   void DidLoseOutputSurface() override;
   void DidSwapBuffers() override;
   void DidSwapBuffersComplete() override;
   void ReclaimResources(const CompositorFrameAck* ack) override;
   void SetMemoryPolicy(const ManagedMemoryPolicy& policy) override;
   void SetTreeActivationCallback(const base::Closure& callback) override;
+  void OnDraw() override;
 
   // Called from LayerTreeImpl.
   void OnCanDrawStateChangedForTree();
 
   // Implementation.
   int id() const { return id_; }
   bool CanDraw() const;
   OutputSurface* output_surface() const { return output_surface_.get(); }
 
   std::string LayerTreeAsJson() const;
@@ skipping 439 matching lines @@
   bool is_likely_to_require_a_draw_;
 
   scoped_ptr<FrameTimingTracker> frame_timing_tracker_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_HOST_IMPL_H_