Remove TextTrackClient interface to simplify TextTrack code.

Source/core/html/track/InbandTextTrack.cpp

 /*
  * Copyright (C) 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 20 matching lines @@
 #include "platform/Logging.h"
 #include "public/platform/WebInbandTextTrack.h"
 #include "public/platform/WebString.h"
 #include <math.h>
 
 using blink::WebInbandTextTrack;
 using blink::WebString;
 
 namespace WebCore {
 
-PassRefPtr<InbandTextTrack> InbandTextTrack::create(Document& document, TextTrackClient* client, WebInbandTextTrack* webTrack)
+PassRefPtr<InbandTextTrack> InbandTextTrack::create(Document& document, WebInbandTextTrack* webTrack)
 {
-    return adoptRef(new InbandTextTrack(document, client, webTrack));
+    return adoptRef(new InbandTextTrack(document, webTrack));
 }
 
-InbandTextTrack::InbandTextTrack(Document& document, TextTrackClient* client, WebInbandTextTrack* webTrack)
-    : TextTrack(document, client, emptyAtom, webTrack->label(), webTrack->language(), webTrack->id(), InBand)
+InbandTextTrack::InbandTextTrack(Document& document, WebInbandTextTrack* webTrack)
+    : TextTrack(document, emptyAtom, webTrack->label(), webTrack->language(), webTrack->id(), InBand)
     , m_webTrack(webTrack)
 {
     m_webTrack->setClient(this);
 
     switch (m_webTrack->kind()) {
     case WebInbandTextTrack::KindSubtitles:
         setKind(TextTrack::subtitlesKeyword());
         break;
     case WebInbandTextTrack::KindCaptions:
         setKind(TextTrack::captionsKeyword());
@@ skipping 28 matching lines @@
 
 void InbandTextTrack::setTrackList(TextTrackList* trackList)
 {
     TextTrack::setTrackList(trackList);
     if (trackList)
         return;
 
     ASSERT(m_webTrack);
     m_webTrack->setClient(0);
     m_webTrack = 0;
-    clearClient();
 }
 
 void InbandTextTrack::addWebVTTCue(double start, double end, const WebString& id, const WebString& content, const WebString& settings)
 {
     RefPtr<VTTCue> cue = VTTCue::create(document(), start, end, content);
     cue->setId(id);
     cue->parseSettings(settings);
     addCue(cue);
 }
 
 } // namespace WebCore