Implement tail processing for AudioNodes

third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.h

Index: third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.h
diff --git a/third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.h b/third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.h
index 94dfd95ce2684a8d16f1956213ceb6e2c0fbe493..23b48c585d8b8a99707764c280be077c2f2ce3f2 100644
--- a/third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.h
+++ b/third_party/WebKit/Source/modules/webaudio/DeferredTaskHandler.h
@@ -105,6 +105,14 @@ class MODULES_EXPORT DeferredTaskHandler final
   void RequestToDeleteHandlersOnMainThread();
   void ClearHandlersToBeDeleted();
 
+  // If |node| requires tail processing, add it to the list of tail
+  // nodes so the tail is processed.
+  void AddTailProcessingNode(PassRefPtr<AudioHandler> node);
+
+  // Remove |node| from the list of tail nodes (because the tail
+  // processing is complete).
+  void RemoveTailProcessingNode(PassRefPtr<AudioHandler> node);
+
   //
   // Thread Safety and Graph Locking:
   //
@@ -171,6 +179,10 @@ class MODULES_EXPORT DeferredTaskHandler final
   void HandleDirtyAudioNodeOutputs();
   void DeleteHandlersOnMainThread();
 
+  // Check tail processing nodes and remove any node if the tail has
+  // been processed.
+  void UpdateTailProcessingNodes();
+
   // For the sake of thread safety, we maintain a seperate Vector of automatic
   // pull nodes for rendering in m_renderingAutomaticPullNodes.  It will be
   // copied from m_automaticPullNodes by updateAutomaticPullNodes() at the
@@ -199,6 +211,9 @@ class MODULES_EXPORT DeferredTaskHandler final
   Vector<RefPtr<AudioHandler>> rendering_orphan_handlers_;
   Vector<RefPtr<AudioHandler>> deletable_orphan_handlers_;
 
+  // Nodes that are processing its tail.
+  Vector<RefPtr<AudioHandler>> tail_processing_nodes_;
+
   // Graph locking.
   RecursiveMutex context_graph_mutex_;
   volatile ThreadIdentifier audio_thread_;