Keep AudioSourceNode from premature GC with ScriptWrappable::hasPendingActivity()

third_party/WebKit/Source/modules/webaudio/AudioScheduledSourceNode.cpp

 /*
  * Copyright (C) 2012, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 245 matching lines @@
 EventListener* AudioScheduledSourceNode::onended()
 {
     return getAttributeEventListener(EventTypeNames::ended);
 }
 
 void AudioScheduledSourceNode::setOnended(PassRefPtrWillBeRawPtr<EventListener> listener)
 {
     setAttributeEventListener(EventTypeNames::ended, listener);
 }
 
+bool AudioScheduledSourceNode::hasPendingActivity() const
+{
+    // To avoid the leak, a node should be collected regardless of its
+    // playback state if the context is closed.
+    if (context()->isContextClosed())
+        return false;
+
+    // If a node is scheduled or playing, do not collect the node prematurely
+    // even its reference is out of scope. Then fire onended event if assigned.
+    return audioScheduledSourceHandler().isPlayingOrScheduled();
+}
+
 } // namespace blink