[oilpan] The Node hierarchy should have correct accept method chains

Source/core/html/HTMLAreaElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2009, 2011 Apple Inc. All rights reserved.
  *
  * 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.
  *
@@ skipping 235 matching lines @@
     // The inherited method is not used because it assumes that a render object must exist 
     // for the element to support focus. AREA elements do not have render objects.
     return isLink();
 }
 
 String HTMLAreaElement::target() const
 {
     return getAttribute(targetAttr);
 }
 
+void HTMLAreaElement::acceptHeapVisitor(Visitor* visitor) const
+{
+    HTMLAnchorElement::acceptHeapVisitor(visitor);
 }
+
+}