Use ElementTraversal API in ContainerNode::checkForChildrenAdjacentRuleChanges()

Source/core/dom/ContainerNode.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 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 1098 matching lines @@
     bool hasDirectAdjacentRules = childrenAffectedByDirectAdjacentRules();
     bool hasIndirectAdjacentRules = childrenAffectedByIndirectAdjacentRules();
 
     if (!hasDirectAdjacentRules && !hasIndirectAdjacentRules)
         return;
 
     unsigned forceCheckOfNextElementCount = 0;
     bool forceCheckOfAnyElementSibling = false;
     Document& document = this->document();
 
-    for (Node* child = firstChild(); child; child = child->nextSibling()) {
-        if (!child->isElementNode())
-            continue;
-        Element* element = toElement(child);
-        bool childRulesChanged = element->needsStyleRecalc() && element->styleChangeType() >= SubtreeStyleChange;
+    for (Element* child = ElementTraversal::firstChild(*this); child; child = ElementTraversal::nextSibling(*child)) {
+        bool childRulesChanged = child->needsStyleRecalc() && child->styleChangeType() >= SubtreeStyleChange;
 
         if (forceCheckOfNextElementCount || forceCheckOfAnyElementSibling)
-            element->setNeedsStyleRecalc(SubtreeStyleChange);
-
-        if (forceCheckOfNextElementCount)
-            forceCheckOfNextElementCount--;
+            child->setNeedsStyleRecalc(SubtreeStyleChange);
 
         if (childRulesChanged && hasDirectAdjacentRules)
             forceCheckOfNextElementCount = document.styleEngine()->maxDirectAdjacentSelectors();
+        else if (forceCheckOfNextElementCount)
+            --forceCheckOfNextElementCount;
 
         forceCheckOfAnyElementSibling = forceCheckOfAnyElementSibling || (childRulesChanged && hasIndirectAdjacentRules);
     }
 }
 
 void ContainerNode::checkForSiblingStyleChanges(bool finishedParsingCallback, Node* beforeChange, Node* afterChange, int childCountDelta)
 {
     if (!inActiveDocument() || document().hasPendingForcedStyleRecalc() || styleChangeType() >= SubtreeStyleChange)
         return;
 
@@ skipping 135 matching lines @@
         return true;
 
     if (node->isElementNode() && toElement(node)->shadow())
         return true;
 
     return false;
 }
 #endif
 
 } // namespace WebCore