Refactor Timer classes in preparation for landing FrameTimers.

third_party/WebKit/Source/platform/AsyncMethodRunner.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 115 matching lines @@
 private:
     AsyncMethodRunner(TargetClass* object, TargetMethod method)
         : m_timer(this, &AsyncMethodRunner<TargetClass>::fired)
         , m_object(object)
         , m_method(method)
         , m_suspended(false)
         , m_runWhenResumed(false)
     {
     }
 
-    void fired(Timer<AsyncMethodRunner<TargetClass>>*)
+    void fired(TimerBase*)
     {
         (m_object->*m_method)();
     }
 
     Timer<AsyncMethodRunner<TargetClass>> m_timer;
 
     Member<TargetClass> m_object;
     TargetMethod m_method;
 
     bool m_suspended;
     bool m_runWhenResumed;
 };
 
 } // namespace blink
 
 #endif