Bug 989210 - Consistently make cycle collector to deal with TextTrackManager's member variables. r=reyre

content/html/content/src/TextTrackManager.cpp

@@ -73,7 +73,7 @@ CompareTextTracks::LessThan(TextTrack* aOne, TextTrack* aTwo) const
   return true;
 }
 
-NS_IMPL_CYCLE_COLLECTION_3(TextTrackManager, mTextTracks,
+NS_IMPL_CYCLE_COLLECTION_4(TextTrackManager, mMediaElement, mTextTracks,
                            mPendingTextTracks, mNewCues)
 NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(TextTrackManager, AddRef)
 NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(TextTrackManager, Release)

content/html/content/src/TextTrackManager.h

@@ -89,10 +89,7 @@ public:
   void PopulatePendingList();
 
   // The HTMLMediaElement that this TextTrackManager manages the TextTracks of.
-  // This is a weak reference as the life time of TextTrackManager is dependent
-  // on the HTMLMediaElement, so it should not be trying to hold the
-  // HTMLMediaElement alive.
-  HTMLMediaElement* mMediaElement;
+  nsRefPtr<HTMLMediaElement> mMediaElement;
 private:
   // List of the TextTrackManager's owning HTMLMediaElement's TextTracks.
   nsRefPtr<TextTrackList> mTextTracks;