[wrapper-tracing] Add NodeList write barriers

third_party/WebKit/Source/core/dom/NodeRareData.h

 /*
  * Copyright (C) 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2008 David Smith <catfish.man@gmail.com>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 58 matching lines @@
     return new NodeRareData(layoutObject);
   }
 
   void clearNodeLists() { m_nodeLists.clear(); }
   NodeListsNodeData* nodeLists() const { return m_nodeLists.get(); }
   // ensureNodeLists() and a following NodeListsNodeData functions must be
   // wrapped with a ThreadState::GCForbiddenScope in order to avoid an
   // initialized m_nodeLists is cleared by NodeRareData::traceAfterDispatch().
   NodeListsNodeData& ensureNodeLists() {
     DCHECK(ThreadState::current()->isGCForbidden());
-    if (!m_nodeLists)
+    if (!m_nodeLists) {
       m_nodeLists = NodeListsNodeData::create();
+      ScriptWrappableVisitor::writeBarrier(this, m_nodeLists);
+    }
     return *m_nodeLists;
   }
 
   NodeMutationObserverData* mutationObserverData() {
     return m_mutationObserverData.get();
   }
   NodeMutationObserverData& ensureMutationObserverData() {
     if (!m_mutationObserverData) {
       m_mutationObserverData = NodeMutationObserverData::create();
       ScriptWrappableVisitor::writeBarrier(this, m_mutationObserverData);
@@ skipping 52 matching lines @@
   unsigned m_elementFlags : NumberOfElementFlags;
   unsigned m_restyleFlags : NumberOfDynamicRestyleFlags;
 
  protected:
   unsigned m_isElementRareData : 1;
 };
 
 }  // namespace blink
 
 #endif  // NodeRareData_h