Making OutputSurface a begin frame source and vsync source.

cc/scheduler/scheduler.h

Index: cc/scheduler/scheduler.h
diff --git a/cc/scheduler/scheduler.h b/cc/scheduler/scheduler.h
index 73197b72c30efcd0afb4c730906893234c3d3486..52f70e05e8bf55d309eaae5497a2b3bb758796d5 100644
--- a/cc/scheduler/scheduler.h
+++ b/cc/scheduler/scheduler.h
@@ -14,6 +14,7 @@
 #include "base/time/time.h"
 #include "cc/base/cc_export.h"
 #include "cc/output/begin_frame_args.h"
+#include "cc/output/output_surface.h"
 #include "cc/scheduler/delay_based_time_source.h"
 #include "cc/scheduler/draw_result.h"
 #include "cc/scheduler/frame_source.h"
@@ -31,7 +32,6 @@ namespace cc {
 
 class SchedulerClient {
  public:
-  virtual BeginFrameSource* GetExternalBeginFrameSource() = 0;
   virtual void WillBeginImplFrame(const BeginFrameArgs& args) = 0;
   virtual void ScheduledActionSendBeginMainFrame() = 0;
   virtual DrawResult ScheduledActionDrawAndSwapIfPossible() = 0;
@@ -99,7 +99,7 @@ class CC_EXPORT Scheduler : public BeginFrameObserver {
 
   void DidManageTiles();
   void DidLoseOutputSurface();
-  void DidCreateAndInitializeOutputSurface();
+  void DidCreateAndInitializeOutputSurface(OutputSurface* output_surface);
 
   // Tests do not want to shut down until all possible BeginMainFrames have
   // occured to prevent flakiness.
@@ -139,6 +139,9 @@ class CC_EXPORT Scheduler : public BeginFrameObserver {
   base::TimeTicks LastBeginImplFrameTime();
 
   ui::CompositorVSyncManager::Observer* vsync_observer_ = NULL;
+
+  void UpdateActiveFrameSource();
+
   scoped_ptr<BeginFrameSourceMultiplexer> frame_source_;
   BeginFrameSource* primary_frame_source_ = NULL;
   BeginFrameSource* background_frame_source_ = NULL;