Bug 1267036: Force recalculation of readyState when download is progressing. r=jwwang

Under some circumstances, the MP3Demuxer is unable to calculate the buffered range which would prevent the readyState value to be recalculated. To get around this we force recalculation when the progress event is fired.

MozReview-Commit-ID: DTaxJjOX4JU

dom/html/HTMLMediaElement.cpp

@@ -3831,6 +3831,8 @@ void HTMLMediaElement::CheckProgress(bool aHaveNewProgress)
         ChangeDelayLoadStatus(true);
       }
     }
+    // Download statistics may have been updated, force a recheck of the readyState.
+    UpdateReadyStateInternal();
   }
 
   if (now - mDataTime >= TimeDuration::FromMilliseconds(STALL_MS)) {