Bug 1286041 - Assert audio callback is not called in initialized state. r=jwwang

dom/media/AudioStream.cpp

@@ -400,9 +400,12 @@ AudioStream::Start()
 {
   MonitorAutoLock mon(mMonitor);
   MOZ_ASSERT(mState == INITIALIZED);
+  mState = STARTED;
   auto r = InvokeCubeb(cubeb_stream_start);
-  mState = r == CUBEB_OK ? STARTED : ERRORED;
-  LOG("started, state %s", mState == STARTED ? "STARTED" : "ERRORED");
+  if (r != CUBEB_OK) {
+    mState = ERRORED;
+  }
+  LOG("started, state %s", mState == STARTED ? "STARTED" : mState == DRAINED ? "DRAINED" : "ERRORED");
 }
 
 void
@@ -594,13 +597,7 @@ AudioStream::DataCallback(void* aBuffer, long aFrames)
   auto writer = AudioBufferWriter(
     reinterpret_cast<AudioDataValue*>(aBuffer), mOutChannels, aFrames);
 
-  // FIXME: cubeb_pulse sometimes calls us before cubeb_stream_start() is called.
-  // We don't want to consume audio data until Start() is called by the client.
-  if (mState == INITIALIZED) {
-    NS_WARNING("data callback fires before cubeb_stream_start() is called");
-    mAudioClock.UpdateFrameHistory(0, aFrames);
-    return writer.WriteZeros(aFrames);
-  }
+  MOZ_ASSERT(mState != INITIALIZED);
 
   // NOTE: wasapi (others?) can call us back *after* stop()/Shutdown() (mState == SHUTDOWN)
   // Bug 996162