Simplify Node::invalidateNodeListCachesInAncestors()'s code a bit

Source/core/dom/Node.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 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 846 matching lines @@
     // Modifications to attributes that are not associated with an Element can't invalidate NodeList caches.
     if (attrName && !attributeOwnerElement)
         return;
 
     if (!document().shouldInvalidateNodeListCaches(attrName))
         return;
 
     document().invalidateNodeListCaches(attrName);
 
     for (Node* node = this; node; node = node->parentNode()) {
-        if (!node->hasRareData())
-            continue;
-        NodeRareData* data = node->rareData();
-        if (data->nodeLists())
-            data->nodeLists()->invalidateCaches(attrName);
+        if (NodeListsNodeData* lists = node->nodeLists())
+            lists->invalidateCaches(attrName);
     }
 }
 
 NodeListsNodeData* Node::nodeLists()
 {
     return hasRareData() ? rareData()->nodeLists() : 0;
 }
 
 void Node::clearNodeLists()
 {
@@ skipping 1699 matching lines @@
         node->showTreeForThis();
 }
 
 void showNodePath(const WebCore::Node* node)
 {
     if (node)
         node->showNodePathForThis();
 }
 
 #endif