Remove MediaControls::textTracksChanged

Source/core/html/shadow/MediaControls.cpp

 /*
  * Copyright (C) 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2011, 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.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 338 matching lines @@
 }
 
 void MediaControls::refreshClosedCaptionsButtonVisibility()
 {
     if (mediaElement().hasClosedCaptions())
         m_toggleClosedCaptionsButton->show();
     else
         m_toggleClosedCaptionsButton->hide();
 }
 
-void MediaControls::textTracksChanged()
-{
-    refreshClosedCaptionsButtonVisibility();
-}
-
 static Element* elementFromCenter(Element& element)
 {
     RefPtrWillBeRawPtr<ClientRect> clientRect = element.getBoundingClientRect();
     int centerX = static_cast<int>((clientRect->left() + clientRect->right()) / 2);
     int centerY = static_cast<int>((clientRect->top() + clientRect->bottom()) / 2);
 
     return element.document().elementFromPoint(centerX , centerY);
 }
 
 void MediaControls::tryShowOverlayCastButton()
@@ skipping 197 matching lines @@
     visitor->trace(m_toggleClosedCaptionsButton);
     visitor->trace(m_fullScreenButton);
     visitor->trace(m_durationDisplay);
     visitor->trace(m_enclosure);
     visitor->trace(m_castButton);
     visitor->trace(m_overlayCastButton);
     HTMLDivElement::trace(visitor);
 }
 
 }