Bug 1100803 - Re-create a decoded media stream if necessary. r=roc

dom/media/MediaDecoder.cpp

@@ -266,6 +266,14 @@ MediaDecoder::DecodedStreamGraphListener::NotifyEvent(MediaStreamGraph* aGraph,
     aGraph->DispatchToMainThreadAfterStreamStateUpdate(event.forget());
   }
 }
+
+void MediaDecoder::RecreateDecodedStreamIfNecessary(int64_t aStartTimeUSecs)
+{
+  if (mInitialAudioCaptured) {
+    RecreateDecodedStream(aStartTimeUSecs);
+  }
+}
+
 void MediaDecoder::DestroyDecodedStream()
 {
   MOZ_ASSERT(NS_IsMainThread());

dom/media/MediaDecoder.h

@@ -851,6 +851,9 @@ public:
   // The decoder monitor must be held.
   bool IsLogicallyPlaying();
 
+  // Re-create a decoded stream if audio being captured
+  void RecreateDecodedStreamIfNecessary(int64_t aStartTimeUSecs);
+
 #ifdef MOZ_EME
   // This takes the decoder monitor.
   virtual nsresult SetCDMProxy(CDMProxy* aProxy) MOZ_OVERRIDE;

dom/media/MediaDecoderStateMachine.cpp

@@ -1624,9 +1624,7 @@ MediaDecoderStateMachine::StartSeek(const SeekTarget& aTarget)
 
   DECODER_LOG("Changed state to SEEKING (to %lld)", mSeekTarget.mTime);
   SetState(DECODER_STATE_SEEKING);
-  if (mDecoder->GetDecodedStream()) {
-    mDecoder->RecreateDecodedStream(seekTime - mStartTime);
-  }
+  mDecoder->RecreateDecodedStreamIfNecessary(seekTime - mStartTime);
   ScheduleStateMachine();
 }