Bug 943461. Part 1: A stream is fully finished when all its tracks have finished playing out. r=padenot

--HG--
extra : rebase_source : 0efa4353ea22ffd52d550331623098d275382148

content/media/MediaStreamGraph.cpp

@@ -416,7 +416,10 @@ MediaStreamGraphImpl::UpdateCurrentTime()
 
   for (uint32_t i = 0; i < streamsReadyToFinish.Length(); ++i) {
     MediaStream* stream = streamsReadyToFinish[i];
-    if (StreamTimeToGraphTime(stream, stream->GetBufferEnd()) <= mCurrentTime) {
+    // The stream is fully finished when all of its track data has been played
+    // out.
+    if (mCurrentTime >=
+          stream->StreamTimeToGraphTime(stream->GetStreamBuffer().GetAllTracksEnd()))  {
       stream->mNotifiedFinished = true;
       stream->mLastPlayedVideoFrame.SetNull();
       for (uint32_t j = 0; j < stream->mListeners.Length(); ++j) {

content/media/StreamBuffer.cpp

@@ -46,6 +46,25 @@ StreamBuffer::GetEnd() const
   return t;
 }
 
+StreamTime
+StreamBuffer::GetAllTracksEnd() const
+{
+  StreamTime t = 0;
+  for (uint32_t i = 0; i < mTracks.Length(); ++i) {
+    Track* track = mTracks[i];
+    if (!track->IsEnded()) {
+      return STREAM_TIME_MAX;
+    }
+    t = std::max(t, track->GetEndTimeRoundDown());
+  }
+  if (t > mTracksKnownTime) {
+    // It can't be later then mTracksKnownTime, since a track might be added
+    // after that.
+    return STREAM_TIME_MAX;
+  }
+  return t;
+}
+
 StreamBuffer::Track*
 StreamBuffer::FindTrack(TrackID aID)
 {

content/media/StreamBuffer.h

@@ -224,6 +224,13 @@ public:
    */
   StreamTime GetEnd() const;
 
+  /**
+   * Returns the earliest time >= 0 at which all tracks have ended
+   * and all their data has been played out and no new tracks can be added,
+   * or STREAM_TIME_MAX if there is no such time.
+   */
+  StreamTime GetAllTracksEnd() const;
+
 #ifdef DEBUG
   void DumpTrackInfo() const;
 #endif