Oilpan: move RenderObjects off heap.

Source/core/rendering/RenderTextFragment.cpp

 /*
  * (C) 1999 Lars Knoll (knoll@kde.org)
  * (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007 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 47 matching lines @@
 }
 
 void RenderTextFragment::destroy()
 {
     if (m_isRemainingTextRenderer && m_firstLetterPseudoElement)
         m_firstLetterPseudoElement->setRemainingTextRenderer(nullptr);
     m_firstLetterPseudoElement = nullptr;
     RenderText::destroy();
 }
 
-void RenderTextFragment::trace(Visitor* visitor)
-{
-    visitor->trace(m_firstLetterPseudoElement);
-    RenderText::trace(visitor);
-}
-
 PassRefPtr<StringImpl> RenderTextFragment::completeText() const
 {
     Text* text = associatedTextNode();
     return text ? text->dataImpl() : contentString();
 }
 
 void RenderTextFragment::setContentString(StringImpl* str)
 {
     m_contentString = str;
     setText(str);
@@ skipping 67 matching lines @@
         FirstLetterPseudoElement* pseudo = toFirstLetterPseudoElement(node);
         RenderObject* nextRenderer = FirstLetterPseudoElement::firstLetterTextRenderer(*pseudo);
         if (!nextRenderer)
             return nullptr;
         node = nextRenderer->node();
     }
     return (node && node->isTextNode()) ? toText(node) : nullptr;
 }
 
 } // namespace blink