Refactor Timer classes in preparation for landing FrameTimers.

third_party/WebKit/Source/core/animation/CompositorPendingAnimations.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 42 matching lines @@
 
     void add(Animation*);
     // Returns whether we are waiting for an animation to start and should
     // service again on the next frame.
     bool update(bool startOnCompositor = true);
     void notifyCompositorAnimationStarted(double monotonicAnimationStartTime, int compositorGroup = 0);
 
     DECLARE_TRACE();
 
 private:
-    void timerFired(Timer<CompositorPendingAnimations>*) { update(false); }
+    void timerFired(TimerBase*) { update(false); }
 
     HeapVector<Member<Animation>> m_pending;
     HeapVector<Member<Animation>> m_waitingForCompositorAnimationStart;
     Timer<CompositorPendingAnimations> m_timer;
     int m_compositorGroup;
 };
 
 } // namespace blink
 
 #endif