Backed out changeset 4757a1d4a23e (bug 1113282) for e10s M1 test failures

dom/media/mediasource/MediaSourceReader.cpp

@@ -327,7 +327,6 @@ MediaSourceReader::Shutdown()
 void
 MediaSourceReader::ContinueShutdown()
 {
-  ReentrantMonitorAutoEnter mon(mDecoder->GetReentrantMonitor());
   if (mTrackBuffers.Length()) {
     mTrackBuffers[0]->Shutdown()->Then(GetTaskQueue(), __func__, this,
                                        &MediaSourceReader::ContinueShutdown,

dom/media/mediasource/TrackBuffer.cpp

@@ -39,14 +39,12 @@ TrackBuffer::TrackBuffer(MediaSourceDecoder* aParentDecoder, const nsACString& a
   : mParentDecoder(aParentDecoder)
   , mType(aType)
   , mLastStartTimestamp(0)
-  , mShutdown(false)
 {
   MOZ_COUNT_CTOR(TrackBuffer);
   mParser = ContainerParser::CreateForMIMEType(aType);
   mTaskQueue = new MediaTaskQueue(GetMediaDecodeThreadPool());
   aParentDecoder->AddTrackBuffer(this);
   mDecoderPerSegment = Preferences::GetBool("media.mediasource.decoder-per-segment", false);
-  MSE_DEBUG("TrackBuffer(%p) created for parent decoder %p", this, aParentDecoder);
 }
 
 TrackBuffer::~TrackBuffer()
@@ -103,9 +101,6 @@ private:
 nsRefPtr<ShutdownPromise>
 TrackBuffer::Shutdown()
 {
-  mParentDecoder->GetReentrantMonitor().AssertCurrentThreadIn();
-  mShutdown = true;
-
   MOZ_ASSERT(mShutdownPromise.IsEmpty());
   nsRefPtr<ShutdownPromise> p = mShutdownPromise.Ensure(__func__);
 
@@ -375,42 +370,23 @@ TrackBuffer::QueueInitializeDecoder(SourceBufferDecoder* aDecoder)
 void
 TrackBuffer::InitializeDecoder(SourceBufferDecoder* aDecoder)
 {
-  // ReadMetadata may block the thread waiting on data, so we must be able
-  // to leave the monitor while we call it. For the rest of this function
-  // we want to hold the monitor though, since we run on a different task queue
-  // from the reader and interact heavily with it.
-  mParentDecoder->GetReentrantMonitor().AssertNotCurrentThreadIn();
-  ReentrantMonitorAutoEnter mon(mParentDecoder->GetReentrantMonitor());
-
-  // We may be shut down at any time by the reader on another thread. So we need
-  // to check for this each time we acquire the monitor. If that happens, we
-  // need to abort immediately, because the reader has forgotten about us, and
-  // important pieces of our state (like mTaskQueue) have also been torn down.
-  if (mShutdown) {
-    MSE_DEBUG("TrackBuffer(%p) was shut down. Aborting initialization.", this);
-    return;
-  }
-
   MOZ_ASSERT(mTaskQueue->IsCurrentThreadIn());
+
+  // ReadMetadata may block the thread waiting on data, so it must not be
+  // called with the monitor held.
+  mParentDecoder->GetReentrantMonitor().AssertNotCurrentThreadIn();
+
   MediaDecoderReader* reader = aDecoder->GetReader();
   MSE_DEBUG("TrackBuffer(%p): Initializing subdecoder %p reader %p",
             this, aDecoder, reader);
 
   MediaInfo mi;
   nsAutoPtr<MetadataTags> tags; // TODO: Handle metadata.
-  nsresult rv;
+  nsresult rv = reader->ReadMetadata(&mi, getter_Transfers(tags));
-  {
-    ReentrantMonitorAutoExit mon(mParentDecoder->GetReentrantMonitor());
-    rv = reader->ReadMetadata(&mi, getter_Transfers(tags));
-  }
-
   reader->SetIdle();
-  if (mShutdown) {
-    MSE_DEBUG("TrackBuffer(%p) was shut down while reading metadata. Aborting initialization.", this);
-    return;
-  }
 
   if (NS_SUCCEEDED(rv) && reader->IsWaitingOnCDMResource()) {
+    ReentrantMonitorAutoEnter mon(mParentDecoder->GetReentrantMonitor());
     mWaitingDecoders.AppendElement(aDecoder);
     return;
   }
@@ -466,7 +442,7 @@ TrackBuffer::ValidateTrackFormats(const MediaInfo& aInfo)
 bool
 TrackBuffer::RegisterDecoder(SourceBufferDecoder* aDecoder)
 {
-  mParentDecoder->GetReentrantMonitor().AssertCurrentThreadIn();
+  ReentrantMonitorAutoEnter mon(mParentDecoder->GetReentrantMonitor());
   const MediaInfo& info = aDecoder->GetReader()->GetMediaInfo();
   // Initialize the track info since this is the first decoder.
   if (mInitializedDecoders.IsEmpty()) {

dom/media/mediasource/TrackBuffer.h

@@ -163,7 +163,6 @@ private:
   void ContinueShutdown();
   MediaPromiseHolder<ShutdownPromise> mShutdownPromise;
   bool mDecoderPerSegment;
-  bool mShutdown;
 };
 
 } // namespace mozilla