Bug 1625372 permit ForceShutDown() on a realtime graph r=padenot

Depends on D74812

Differential Revision: https://phabricator.services.mozilla.com/D74813

dom/media/MediaTrackGraph.cpp

@@ -1618,9 +1618,8 @@ class MediaTrackGraphShutDownRunnable : public Runnable {
       // mGraph is no longer needed, so delete it.
       mGraph->Destroy();
     } else {
-      // The graph is not empty.  We must be in a forced shutdown, either for
-      // process shutdown or a non-realtime graph that has finished
-      // processing. Some later AppendMessage will detect that the graph has
+      // The graph is not empty.  We must be in a forced shutdown.
+      // Some later AppendMessage will detect that the graph has
       // been emptied, and delete it.
       NS_ASSERTION(mGraph->mForceShutDownReceived, "Not in forced shutdown?");
       mGraph->LifecycleStateRef() =
@@ -3129,12 +3128,10 @@ MediaTrackGraph* MediaTrackGraph::CreateNonRealtimeInstance(
   return graph;
 }
 
-void MediaTrackGraph::DestroyNonRealtimeInstance(MediaTrackGraph* aGraph) {
+void MediaTrackGraph::ForceShutDown() {
   MOZ_ASSERT(NS_IsMainThread(), "Main thread only");
-  MOZ_ASSERT(aGraph->IsNonRealtime(),
-             "Should not destroy the global graph here");
 
-  MediaTrackGraphImpl* graph = static_cast<MediaTrackGraphImpl*>(aGraph);
+  MediaTrackGraphImpl* graph = static_cast<MediaTrackGraphImpl*>(this);
 
   graph->ForceShutDown();
 }

dom/media/MediaTrackGraph.h

@@ -1026,7 +1026,7 @@ class MediaTrackGraph {
   AbstractThread* AbstractMainThread();
 
   // Idempotent
-  static void DestroyNonRealtimeInstance(MediaTrackGraph* aGraph);
+  void ForceShutDown();
 
   virtual nsresult OpenAudioInput(CubebUtils::AudioDeviceID aID,
                                   AudioDataListener* aListener) = 0;

dom/media/MediaTrackGraphImpl.h

@@ -174,7 +174,8 @@ class MediaTrackGraphImpl : public MediaTrackGraph,
    * Make this MediaTrackGraph enter forced-shutdown state. This state
    * will be noticed by the media graph thread, which will shut down all tracks
    * and other state controlled by the media graph thread.
-   * This is called during application shutdown.
+   * This is called during application shutdown, and on document unload if an
+   * AudioContext is using the graph.
    */
   void ForceShutDown();
 
@@ -841,13 +842,13 @@ class MediaTrackGraphImpl : public MediaTrackGraph,
    * creation after this point will create a new graph. An async event is
    * dispatched to Shutdown() the graph's threads and then delete the graph
    * object.
-   * 2) Forced shutdown at application shutdown, or completion of a
-   * non-realtime graph. A flag is set, RunThread() detects the flag and
-   * exits, the next RunInStableState() detects the flag, and dispatches the
-   * async event to Shutdown() the graph's threads. However the graph object
-   * is not deleted. New messages for the graph are processed synchronously on
-   * the main thread if necessary. When the last track is destroyed, the
-   * graph object is deleted.
+   * 2) Forced shutdown at application shutdown, completion of a non-realtime
+   * graph, or document unload. A flag is set, RunThread() detects the flag
+   * and exits, the next RunInStableState() detects the flag, and dispatches
+   * the async event to Shutdown() the graph's threads. However the graph
+   * object is not deleted. New messages for the graph are processed
+   * synchronously on the main thread if necessary. When the last track is
+   * destroyed, the graph object is deleted.
    *
    * This should be kept in sync with the LifecycleState_str array in
    * MediaTrackGraph.cpp
@@ -902,9 +903,8 @@ class MediaTrackGraphImpl : public MediaTrackGraph,
   }
 
   /**
-   * True when we need to do a forced shutdown, during process shutdown or
-   * when shutting down a non-realtime graph, and the graph thread has
-   * received the message.  This is checked in the decision to shut down the
+   * True once the graph thread has received the message from ForceShutDown().
+   * This is checked in the decision to shut down the
    * graph thread so that control messages dispatched before forced shutdown
    * are processed on the graph thread.
    * Only set on the graph thread.

dom/media/webaudio/AudioDestinationNode.cpp

@@ -499,7 +499,7 @@ void AudioDestinationNode::OfflineShutdown() {
              "Should only be called on a valid OfflineAudioContext");
 
   if (mTrack) {
-    MediaTrackGraph::DestroyNonRealtimeInstance(mTrack->Graph());
+    mTrack->Graph()->MediaTrackGraph::ForceShutDown();
     mOfflineRenderingRef.Drop(this);
   }
 }