Decouple BrowserCompositorOutputSurface from BeginFrameSource.

ui/compositor/compositor_vsync_manager.h

Index: ui/compositor/compositor_vsync_manager.h
diff --git a/ui/compositor/compositor_vsync_manager.h b/ui/compositor/compositor_vsync_manager.h
index 54bcc1a1d295f4d7bc7c68dd9bb1511b8180b78c..4d2a8244d7e1f70ff6e92ab42bc4e537b45f8567 100644
--- a/ui/compositor/compositor_vsync_manager.h
+++ b/ui/compositor/compositor_vsync_manager.h
@@ -10,6 +10,7 @@
 #include "base/observer_list.h"
 #include "base/synchronization/lock.h"
 #include "base/time/time.h"
+#include "cc/scheduler/vsync_observer.h"
 #include "ui/compositor/compositor_export.h"
 
 namespace ui {
@@ -20,12 +21,6 @@ namespace ui {
 class COMPOSITOR_EXPORT CompositorVSyncManager
     : public base::RefCounted<CompositorVSyncManager> {
  public:
-  class Observer {
-   public:
-    virtual void OnUpdateVSyncParameters(base::TimeTicks timebase,
-                                         base::TimeDelta interval) = 0;
-  };
-
   CompositorVSyncManager();
 
   // The "authoritative" vsync interval, if provided, will override |interval|
@@ -42,8 +37,8 @@ class COMPOSITOR_EXPORT CompositorVSyncManager
   void UpdateVSyncParameters(base::TimeTicks timebase,
                              base::TimeDelta interval);
 
-  void AddObserver(Observer* observer);
-  void RemoveObserver(Observer* observer);
+  void AddObserver(cc::VSyncObserver* observer);
+  void RemoveObserver(cc::VSyncObserver* observer);
 
  private:
   friend class base::RefCounted<CompositorVSyncManager>;
@@ -52,7 +47,7 @@ class COMPOSITOR_EXPORT CompositorVSyncManager
 
   void NotifyObservers(base::TimeTicks timebase, base::TimeDelta interval);
 
-  base::ObserverList<Observer> observer_list_;
+  base::ObserverList<cc::VSyncObserver> observer_list_;
 
   base::TimeTicks last_timebase_;
   base::TimeDelta last_interval_;