Remove newMediaPlaybackUi flag from content/ and Blink.

third_party/WebKit/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
@@ skipping 461 matching lines @@
   void configureMediaControls();
 
   TextTrackContainer& ensureTextTrackContainer();
 
   EventDispatchHandlingState* preDispatchEventHandler(Event*) final;
 
   void changeNetworkStateFromLoadingToIdle();
 
   bool isAutoplaying() const { return m_autoplaying; }
 
-  void setAllowHiddenVolumeControls(bool);
-
   WebMediaPlayer::CORSMode corsMode() const;
 
   // Returns the "direction of playback" value as specified in the HTML5 spec.
   enum DirectionOfPlayback { Backward, Forward };
   DirectionOfPlayback getDirectionOfPlayback() const;
 
   // Creates placeholder AudioTrack and/or VideoTrack objects when
   // WebMemediaPlayer objects advertise they have audio and/or video, but don't
   // explicitly signal them via addAudioTrack() and addVideoTrack().
   // FIXME: Remove this once all WebMediaPlayer implementations properly report
@@ skipping 235 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