Bug 1270323: P1. Don't reset flag indicating that new data was received. r=cpearce

A bit of a shot in the dark, but it is possible that data got received but that information got lost as reset was called.

MozReview-Commit-ID: 1KjQeCFsGPJ

--HG--
extra : rebase_source : 3a522045bde0658fdfeccbf4d0cac11b43bc35d7

dom/media/MediaFormatReader.h

@@ -374,7 +374,6 @@ private:
       MOZ_ASSERT(mOwner->OnTaskQueue());
       mDemuxEOS = false;
       mWaitingForData = false;
-      mReceivedNewData = false;
       mDiscontinuity = true;
       mQueuedSamples.Clear();
       mDecodingRequested = false;