Bug 1441779 - Part 1: Change nsTArray<SourceBufferTask> to nsTArray<RefPtr<SourceBufferTask>> r=gerald

MozReview-Commit-ID: 8lV4Pp9p7Ch

--HG--
extra : rebase_source : b149b6ed15f88b9ee8af8ec553a57a8ccec3dafd

dom/media/mediasource/TrackBuffersManager.h

@@ -57,7 +57,7 @@ public:
     return task.forget();
   }
 
-  nsTArray<SourceBufferTask>::size_type Length() const
+  nsTArray<RefPtr<SourceBufferTask>>::size_type Length() const
   {
     return mQueue.Length();
   }