Merge back LayoutLayerModelObject into RenderBoxModelObject

Source/core/layout/LayerStackingNode.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 141 matching lines @@
     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()) {
         RenderView* view = renderer()->view();
         for (LayoutObject* child = view->firstChild(); child; child = child->nextSibling()) {
             Element* childElement = (child->node() && child->node()->isElementNode()) ? toElement(child->node()) : 0;
             if (childElement && childElement->isInTopLayer()) {
-                Layer* layer = toLayoutLayerModelObject(child)->layer();
+                Layer* layer = toLayoutBoxModelObject(child)->layer();
                 // Create the buffer if it doesn't exist yet.
                 if (!m_posZOrderList)
                     m_posZOrderList = adoptPtr(new Vector<LayerStackingNode*>);
                 m_posZOrderList->append(layer->stackingNode());
             }
         }
     }
 
 #if ENABLE(ASSERT)
     updateStackingParentForZOrderLists(this);
@@ skipping 141 matching lines @@
 LayerStackingNode* LayerStackingNode::ancestorStackingContextNode() const
 {
     for (Layer* ancestor = layer()->parent(); ancestor; ancestor = ancestor->parent()) {
         LayerStackingNode* stackingNode = ancestor->stackingNode();
         if (stackingNode->isStackingContext())
             return stackingNode;
     }
     return 0;
 }
 
-LayoutLayerModelObject* LayerStackingNode::renderer() const
+LayoutBoxModelObject* LayerStackingNode::renderer() const
 {
     return m_layer->renderer();
 }
 
 } // namespace blink