Media Controls: delegate 'volumechange' and 'focusin' handling to an EventListener.

third_party/WebKit/Source/core/html/shadow/MediaControlElements.cpp

 /*
  * Copyright (C) 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 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.
@@ skipping 281 matching lines @@
           UserMetricsAction("Media.Controls.Mute"));
 
     mediaElement().setMuted(!mediaElement().muted());
     event->setDefaultHandled();
   }
 
   MediaControlInputElement::defaultEventHandler(event);
 }
 
 void MediaControlMuteButtonElement::updateDisplayType() {
-  setDisplayType(mediaElement().muted() ? MediaUnMuteButton : MediaMuteButton);
+  // TODO(mlamouri): checking for volume == 0 because the mute button will look
+  // 'muted' when the volume is 0 even if the element is not muted. This allows
+  // the painting and the display type to actually match.
+  setDisplayType((mediaElement().muted() || mediaElement().volume() == 0)
+                     ? MediaUnMuteButton
+                     : MediaMuteButton);
   updateOverflowString();
 }
 
 WebLocalizedString::Name
 MediaControlMuteButtonElement::getOverflowStringName() {
   if (mediaElement().muted())
     return WebLocalizedString::OverflowMenuUnmute;
   return WebLocalizedString::OverflowMenuMute;
 }
 
@@ skipping 722 matching lines @@
 MediaControlCurrentTimeDisplayElement*
 MediaControlCurrentTimeDisplayElement::create(MediaControls& mediaControls) {
   MediaControlCurrentTimeDisplayElement* element =
       new MediaControlCurrentTimeDisplayElement(mediaControls);
   element->setShadowPseudoId(
       AtomicString("-webkit-media-controls-current-time-display"));
   return element;
 }
 
 }  // namespace blink