Refactoring the way begin frame sources inside scheduler work.

cc/trees/layer_tree_host_impl.h

Index: cc/trees/layer_tree_host_impl.h
diff --git a/cc/trees/layer_tree_host_impl.h b/cc/trees/layer_tree_host_impl.h
index 494342e5194f7812e185a2374cd5fcc92ad2efa9..3168fd905470bbe841ae25ce61d6c7a9ac40bfed 100644
--- a/cc/trees/layer_tree_host_impl.h
+++ b/cc/trees/layer_tree_host_impl.h
@@ -32,6 +32,7 @@
 #include "cc/resources/resource_provider.h"
 #include "cc/resources/tile_manager.h"
 #include "cc/scheduler/draw_result.h"
+#include "cc/scheduler/frame_source.h"
 #include "skia/ext/refptr.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/gfx/rect.h"
@@ -43,7 +44,6 @@ class CompositorFrameMetadata;
 class DebugRectHistory;
 class FrameRateCounter;
 class LayerImpl;
-class LayerTreeHostImplTimeSourceAdapter;
 class LayerTreeImpl;
 class MemoryHistory;
 class PageScaleAnimation;
@@ -64,13 +64,10 @@ class LayerTreeHostImplClient {
  public:
   virtual void UpdateRendererCapabilitiesOnImplThread() = 0;
   virtual void DidLoseOutputSurfaceOnImplThread() = 0;
-  virtual void CommitVSyncParameters(base::TimeTicks timebase,
-                                     base::TimeDelta interval) = 0;
   virtual void SetEstimatedParentDrawTime(base::TimeDelta draw_time) = 0;
   virtual void SetMaxSwapsPendingOnImplThread(int max) = 0;
   virtual void DidSwapBuffersOnImplThread() = 0;
   virtual void DidSwapBuffersCompleteOnImplThread() = 0;
-  virtual void BeginFrame(const BeginFrameArgs& args) = 0;
   virtual void OnCanDrawStateChanged(bool can_draw) = 0;
   virtual void NotifyReadyToActivate() = 0;
   // Please call these 3 functions through
@@ -110,6 +107,7 @@ class CC_EXPORT LayerTreeHostImpl
       public OutputSurfaceClient,
       public TopControlsManagerClient,
       public ScrollbarAnimationControllerClient,
+      public BaseBeginFrameSource,
       public base::SupportsWeakPtr<LayerTreeHostImpl> {
  public:
   static scoped_ptr<LayerTreeHostImpl> Create(
@@ -182,7 +180,6 @@ class CC_EXPORT LayerTreeHostImpl
   virtual void UpdateAnimationState(bool start_ready_animations);
   void ActivateAnimations();
   void MainThreadHasStoppedFlinging();
-  void UpdateBackgroundAnimateTicking(bool should_background_tick);
   void DidAnimateScrollOffset();
   void SetViewportDamage(const gfx::Rect& damage_rect);
 
@@ -259,6 +256,10 @@ class CC_EXPORT LayerTreeHostImpl
   virtual void SetTreeActivationCallback(const base::Closure& callback)
       OVERRIDE;
 
+  // BeginFrameSource implementation.
+  virtual void OnGenerateChange(bool generate_frames) OVERRIDE;
+  virtual std::string TypeString() const OVERRIDE;
+
   // Called from LayerTreeImpl.
   void OnCanDrawStateChangedForTree();
 
@@ -284,7 +285,6 @@ class CC_EXPORT LayerTreeHostImpl
   const RendererCapabilitiesImpl& GetRendererCapabilities() const;
 
   virtual bool SwapBuffers(const FrameData& frame);
-  void SetNeedsBeginFrame(bool enable);
   virtual void WillBeginImplFrame(const BeginFrameArgs& args);
   void DidModifyTilePriorities();
 
@@ -606,9 +606,6 @@ class CC_EXPORT LayerTreeHostImpl
 
   scoped_ptr<PageScaleAnimation> page_scale_animation_;
 
-  // This is used for ticking animations slowly when hidden.
-  scoped_ptr<LayerTreeHostImplTimeSourceAdapter> time_source_client_adapter_;
-
   scoped_ptr<FrameRateCounter> fps_counter_;
   scoped_ptr<PaintTimeCounter> paint_time_counter_;
   scoped_ptr<MemoryHistory> memory_history_;