Use TextTrackKind enum in HTMLMediaElement.addTextTrack IDL signature

Source/core/html/HTMLMediaElement.h

 /*
  * Copyright (C) 2007, 2008, 2009, 2010, 2011, 2012, 2013 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 157 matching lines @@
     bool togglePlayStateWillPlay() const;
     void togglePlayState();
 
     AudioTrackList& audioTracks();
     void audioTrackChanged();
 
     VideoTrackList& videoTracks();
     void selectedVideoTrackChanged(blink::WebMediaPlayer::TrackId*);
 
     PassRefPtrWillBeRawPtr<TextTrack> addTextTrack(const AtomicString& kind, const AtomicString& label, const AtomicString& language, ExceptionState&);
-    PassRefPtrWillBeRawPtr<TextTrack> addTextTrack(const AtomicString& kind, const AtomicString& label, ExceptionState& exceptionState) { return addTextTrack(kind, label, emptyAtom, exceptionState); }
-    PassRefPtrWillBeRawPtr<TextTrack> addTextTrack(const AtomicString& kind, ExceptionState& exceptionState) { return addTextTrack(kind, emptyAtom, emptyAtom, exceptionState); }
 
     TextTrackList* textTracks();
     CueList currentlyActiveCues() const { return m_currentlyActiveCues; }
 
     void addTextTrack(TextTrack*);
     void removeTextTrack(TextTrack*);
     void textTracksChanged();
     void notifyMediaPlayerOfTextTrackChanges();
 
     // Implements the "forget the media element's media-resource-specific tracks" algorithm in the HTML5 spec.
@@ skipping 441 matching lines @@
 inline bool isHTMLMediaElement(const HTMLElement& element)
 {
     return isHTMLAudioElement(element) || isHTMLVideoElement(element);
 }
 
 DEFINE_HTMLELEMENT_TYPE_CASTS_WITH_FUNCTION(HTMLMediaElement);
 
 } // namespace blink
 
 #endif // HTMLMediaElement_h