Fix <dialog> centering

Source/WebCore/dom/NodeRenderingContext.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2011 Google 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
@@ skipping 62 matching lines @@
 {
 }
 
 static bool isRendererReparented(const RenderObject* renderer)
 {
     if (!renderer->node()->isElementNode())
         return false;
     if (renderer->style() && !renderer->style()->flowThread().isEmpty())
         return true;
 #if ENABLE(DIALOG_ELEMENT)
-    if (toElement(renderer->node())->isInTopLayer())
+    if (renderer->isDialog())
         return true;
 #endif
     return false;
 }
 
 RenderObject* NodeRenderingContext::nextRenderer() const
 {
     if (RenderObject* renderer = m_node->renderer())
         return renderer->nextSibling();
 
@@ skipping 53 matching lines @@
 
     return 0;
 }
 
 RenderObject* NodeRenderingContext::parentRenderer() const
 {
     if (RenderObject* renderer = m_node->renderer())
         return renderer->parent();
 
 #if ENABLE(DIALOG_ELEMENT)
-    if (m_node->isElementNode() && toElement(m_node)->isInTopLayer()) {
+    if (m_node->hasTagName(dialogTag)) {
         // The parent renderer of top layer elements is the RenderView, but only
         // if the normal parent would have had a renderer.
         // FIXME: This behavior isn't quite right as the spec for top layer
         // only talks about display: none ancestors so putting a <dialog> inside
         // an <optgroup> seems like it should still work even though this check
         // will prevent it.
         if (!m_renderingParent || !m_renderingParent->renderer())
             return 0;
         return m_node->document()->renderView();
     }
@@ skipping 146 matching lines @@
     newRenderer->setFlowThreadState(parentRenderer->flowThreadState());
 
     RenderObject* nextRenderer = this->nextRenderer();
     textNode->setRenderer(newRenderer);
     // Parent takes care of the animations, no need to call setAnimatableStyle.
     newRenderer->setStyle(m_style.release());
     parentRenderer->addChild(newRenderer, nextRenderer);
 }
 
 }