Inherit EventTarget interface instead of duplicating its code

Source/core/html/track/TrackBase.h

 /*
  * Copyright (C) 2011 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 15 matching lines @@
 #ifndef TrackBase_h
 #define TrackBase_h
 
 #include "core/dom/EventTarget.h"
 #include <wtf/RefCounted.h>
 
 namespace WebCore {
 
 class ScriptExecutionContext;
 
-class TrackBase : public RefCounted<TrackBase>, public EventTarget {
+class TrackBase : public EventTarget, public RefCounted<TrackBase> {
 public:
     virtual ~TrackBase();
 
     enum Type { BaseTrack, TextTrack, AudioTrack, VideoTrack };
     Type type() const { return m_type; }
 
     virtual const AtomicString& interfaceName() const;
     virtual ScriptExecutionContext* scriptExecutionContext() const;
     
     using RefCounted<TrackBase>::ref;
@@ skipping 11 matching lines @@
     virtual void refEventTarget() { ref(); }
     virtual void derefEventTarget() { deref(); }
     
     ScriptExecutionContext* m_scriptExecutionContext;
     EventTargetData m_eventTargetData;
 };
 
 } // namespace WebCore
 
 #endif // TrackBase_h