Framework to display disabled mute button when audio fails....

webkit/glue/webmediaplayer_impl.h

 // Copyright (c) 2008-2009 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be found
 // in the LICENSE file.
 //
 // Delegate calls from WebCore::MediaPlayerPrivate to Chrome's video player.
 // It contains PipelineImpl which is the actual media player pipeline, it glues
 // the media player pipeline, data source, audio renderer and renderer.
 // PipelineImpl would creates multiple threads and access some public methods
 // of this class, so we need to be extra careful about concurrent access of
 // methods and members.
@@ skipping 165 matching lines @@
   virtual float maxTimeBuffered() const;
   virtual float maxTimeSeekable() const;
 
   // Methods for painting.
   virtual void setSize(const WebKit::WebSize& size);
 
   virtual void paint(WebKit::WebCanvas* canvas, const WebKit::WebRect& rect);
 
   // True if a video is loaded.
   virtual bool hasVideo() const;
+  virtual bool hasAudio() const;
 
   // Dimensions of the video.
   virtual WebKit::WebSize naturalSize() const;
 
   // Getters of playback state.
   virtual bool paused() const;
   virtual bool seeking() const;
   virtual float duration() const;
   virtual float currentTime() const;
 
@@ skipping 71 matching lines @@
   WebKit::WebMediaPlayerClient* client_;
 
   scoped_refptr<Proxy> proxy_;
 
   DISALLOW_COPY_AND_ASSIGN(WebMediaPlayerImpl);
 };
 
 }  // namespace webkit_glue
 
 #endif  // WEBKIT_GLUE_WEBMEDIAPLAYER_IMPL_H_