add 'slow' prefix to RenderObject's firstChild() / lastChild() methods

Source/core/rendering/RenderLayerStackingNode.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 150 matching lines @@
     // Sort the two lists.
     if (m_posZOrderList)
         std::stable_sort(m_posZOrderList->begin(), m_posZOrderList->end(), compareZIndex);
 
     if (m_negZOrderList)
         std::stable_sort(m_negZOrderList->begin(), m_negZOrderList->end(), compareZIndex);
 
     // Append layers for top layer elements after normal layer collection, to ensure they are on top regardless of z-indexes.
     // The renderers of top layer elements are children of the view, sorted in top layer stacking order.
     if (layer()->isRootLayer()) {
-        RenderObject* view = renderer()->view();
+        RenderView* view = renderer()->view();
         for (RenderObject* child = view->firstChild(); child; child = child->nextSibling()) {
             Element* childElement = (child->node() && child->node()->isElementNode()) ? toElement(child->node()) : 0;
             if (childElement && childElement->isInTopLayer()) {
                 RenderLayer* layer = toRenderLayerModelObject(child)->layer();
                 // Create the buffer if it doesn't exist yet.
                 if (!m_posZOrderList)
                     m_posZOrderList = adoptPtr(new Vector<RenderLayerStackingNode*>);
                 m_posZOrderList->append(layer->stackingNode());
             }
         }
@@ skipping 190 matching lines @@
         return ancestor->stackingNode();
     return 0;
 }
 
 RenderLayerModelObject* RenderLayerStackingNode::renderer() const
 {
     return m_layer->renderer();
 }
 
 } // namespace WebCore