Include HTMLMediaElement.h only where needed

Source/core/html/MediaController.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 23 matching lines @@
 #include "platform/Timer.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/Vector.h"
 
 namespace WebCore {
 
 class Clock;
 class Event;
 class ExceptionState;
-class HTMLMediaElement;
 class ExecutionContext;
 
 class MediaController FINAL : public RefCounted<MediaController>, public ScriptWrappable, public MediaControllerInterface, public EventTargetWithInlineData {
     REFCOUNTED_EVENT_TARGET(MediaController);
 public:
     static PassRefPtr<MediaController> create(ExecutionContext*);
     virtual ~MediaController();
 
     void addMediaElement(HTMLMediaElement*);
     void removeMediaElement(HTMLMediaElement*);
@@ skipping 82 matching lines @@
     bool m_closedCaptionsVisible;
     OwnPtr<Clock> m_clock;
     ExecutionContext* m_executionContext;
     Timer<MediaController> m_timeupdateTimer;
     double m_previousTimeupdateTime;
 };
 
 } // namespace WebCore
 
 #endif