Bug 1238906 - part2 : notify audible state from MDSM to ME. r=jwwang

dom/html/HTMLMediaElement.cpp

@@ -2121,7 +2121,8 @@ HTMLMediaElement::HTMLMediaElement(already_AddRefed<mozilla::dom::NodeInfo>& aNo
     mElementInTreeState(ELEMENT_NOT_INTREE),
     mHasUserInteraction(false),
     mFirstFrameLoaded(false),
-    mDefaultPlaybackStartPosition(0.0)
+    mDefaultPlaybackStartPosition(0.0),
+    mIsAudioTrackAudible(false)
 {
   mAudioChannel = AudioChannelService::GetDefaultAudioChannel();
 
@@ -5177,5 +5178,14 @@ HTMLMediaElement::IsCurrentlyPlaying() const
   return false;
 }
 
+void
+HTMLMediaElement::NotifyAudibleStateChanged(bool aAudible)
+{
+  if (mIsAudioTrackAudible != aAudible) {
+    mIsAudioTrackAudible = aAudible;
+    // To do ...
+  }
+}
+
 } // namespace dom
 } // namespace mozilla