Merge/rename two MediaControlElements into their parent classes

Source/core/html/shadow/MediaControlElementTypes.h

 /*
  * Copyright (C) 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2012 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 109 matching lines @@
     void setCurrentValue(double);
     double currentValue() const { return m_currentValue; }
 
 protected:
     explicit MediaControlTimeDisplayElement(Document&, MediaControlElementType);
 
 private:
     double m_currentValue;
 };
 
-// ----------------------------
-
-class MediaControlMuteButtonElement : public MediaControlInputElement {
-public:
-    void changedMute();
-
-    virtual bool willRespondToMouseClickEvents() OVERRIDE { return true; }
-
-protected:
-    explicit MediaControlMuteButtonElement(Document&, MediaControlElementType);
-
-    virtual void defaultEventHandler(Event*) OVERRIDE;
-
-private:
-    virtual void updateDisplayType() OVERRIDE;
-};
-
-// ----------------------------
-
-class MediaControlVolumeSliderElement : public MediaControlInputElement {
-public:
-    virtual bool willRespondToMouseMoveEvents() OVERRIDE;
-    virtual bool willRespondToMouseClickEvents() OVERRIDE;
-    void setVolume(double);
-
-protected:
-    explicit MediaControlVolumeSliderElement(Document&);
-
-    virtual void defaultEventHandler(Event*) OVERRIDE;
-};
-
 } // namespace WebCore
 
 #endif // MediaControlElementTypes_h