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

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

 /*
  * Copyright (C) 2010, 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 276 matching lines @@
         return nullptr;
 
     return new ScriptProcessorNode(context, sampleRate, bufferSize, numberOfInputChannels, numberOfOutputChannels);
 }
 
 size_t ScriptProcessorNode::bufferSize() const
 {
     return static_cast<ScriptProcessorHandler&>(handler()).bufferSize();
 }
 
+bool ScriptProcessorNode::hasPendingActivity() const
+{
+    // To prevent the node from leaking after the context is closed.
+    if (context()->isContextClosed())
+        return false;
+
+    // If |onaudioprocess| event handler is defined, the node should not be
+    // GCed even if it is out of scope.
+    if (hasEventListeners(EventTypeNames::audioprocess))
+        return true;
+
+    return false;
+}
+
 } // namespace blink