Inherit EventTarget interface instead of duplicating its code

Source/core/html/track/TextTrackList.h

 /*
  * Copyright (C) 2011, 2012 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 22 matching lines @@
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/Vector.h"
 
 namespace WebCore {
 
 class HTMLMediaElement;
 class TextTrack;
 class TextTrackList;
 
-class TextTrackList : public RefCounted<TextTrackList>, public ScriptWrappable, public EventTarget {
+class TextTrackList : public EventTarget, public RefCounted<TextTrackList>, public ScriptWrappable {
 public:
     static PassRefPtr<TextTrackList> create(HTMLMediaElement* owner, ScriptExecutionContext* context)
     {
         return adoptRef(new TextTrackList(owner, context));
     }
     ~TextTrackList();
 
     unsigned length() const;
     int getTrackIndex(TextTrack*);
     int getTrackIndexRelativeToRenderedTracks(TextTrack*);
@@ skipping 40 matching lines @@
     Vector<RefPtr<TextTrack> > m_addTrackTracks;
     Vector<RefPtr<TextTrack> > m_elementTracks;
     Vector<RefPtr<TextTrack> > m_inbandTracks;
 
     int m_dispatchingEvents;
 };
 
 } // namespace WebCore
 
 #endif