Oilpan: Prepare to move RenderObject and RenderObjectChildList to Oilpan heap.

Source/core/rendering/RenderObjectChildList.cpp

 /*
  * Copyright (C) 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. 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
@@ skipping 17 matching lines @@
 #include "core/rendering/RenderObjectChildList.h"
 
 #include "core/accessibility/AXObjectCache.h"
 #include "core/rendering/RenderCounter.h"
 #include "core/rendering/RenderObject.h"
 #include "core/rendering/RenderView.h"
 #include "core/rendering/style/RenderStyle.h"
 
 namespace blink {
 
+void RenderObjectChildList::trace(Visitor* visitor)
+{
+    visitor->trace(m_firstChild);
+    visitor->trace(m_lastChild);
+}
+
 void RenderObjectChildList::destroyLeftoverChildren()
 {
     while (firstChild()) {
         if (firstChild()->isListMarker() || (firstChild()->style()->styleType() == FIRST_LETTER && !firstChild()->isText())) {
             firstChild()->remove();  // List markers are owned by their enclosing list and so don't get destroyed by this container. Similarly, first letters are destroyed by their remaining text fragment.
         } else {
             // Destroy any anonymous children remaining in the render tree, as well as implicit (shadow) DOM elements like those used in the engine-based text fields.
             if (firstChild()->node())
                 firstChild()->node()->setRenderer(0);
             firstChild()->destroy();
@@ skipping 112 matching lines @@
 
     newChild->setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation();
     if (!owner->normalChildNeedsLayout())
         owner->setChildNeedsLayout(); // We may supply the static position for an absolute positioned child.
 
     if (AXObjectCache* cache = owner->document().axObjectCache())
         cache->childrenChanged(owner);
 }
 
 } // namespace blink