Consistently use ElementTraversal API when looking for an Element

Source/core/css/RuleFeature.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
@@ skipping 18 matching lines @@
 #include "config.h"
 #include "core/css/RuleFeature.h"
 
 #include "HTMLNames.h"
 #include "RuntimeEnabledFeatures.h"
 #include "core/css/CSSSelector.h"
 #include "core/css/CSSSelectorList.h"
 #include "core/css/RuleSet.h"
 #include "core/dom/Document.h"
 #include "core/dom/Element.h"
+#include "core/dom/ElementTraversal.h"
 #include "core/dom/Node.h"
 #include "core/dom/shadow/ElementShadow.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "wtf/BitVector.h"
 
 namespace WebCore {
 
 static bool isSkippableComponentForInvalidation(const CSSSelector& selector)
 {
     if (selector.matchesPseudoElement() || selector.pseudoType() == CSSSelector::PseudoHost)
@@ skipping 304 matching lines @@
         }
     }
     document.clearChildNeedsStyleInvalidation();
     m_pendingInvalidationMap.clear();
 }
 
 bool RuleFeatureSet::invalidateStyleForClassChangeOnChildren(Element* element, Vector<AtomicString>& invalidationClasses, bool foundInvalidationSet)
 {
     bool someChildrenNeedStyleRecalc = false;
     for (ShadowRoot* root = element->youngestShadowRoot(); root; root = root->olderShadowRoot()) {
-        for (Node* child = root->firstChild(); child; child = child->nextSibling()) {
-            if (child->isElementNode()) {
-                Element* childElement = toElement(child);
-                bool childRecalced = invalidateStyleForClassChange(childElement, invalidationClasses, foundInvalidationSet);
-                someChildrenNeedStyleRecalc = someChildrenNeedStyleRecalc || childRecalced;
-            }
+        for (Element* child = ElementTraversal::firstWithin(*root); child; child = ElementTraversal::nextSibling(*child)) {
+            bool childRecalced = invalidateStyleForClassChange(child, invalidationClasses, foundInvalidationSet);
+            someChildrenNeedStyleRecalc = someChildrenNeedStyleRecalc || childRecalced;
         }
     }
-    for (Node* child = element->firstChild(); child; child = child->nextSibling()) {
-        if (child->isElementNode()) {
-            Element* childElement = toElement(child);
-            bool childRecalced = invalidateStyleForClassChange(childElement, invalidationClasses, foundInvalidationSet);
-            someChildrenNeedStyleRecalc = someChildrenNeedStyleRecalc || childRecalced;
-        }
+    for (Element* child = ElementTraversal::firstWithin(*element); child; child = ElementTraversal::nextSibling(*child)) {
+        bool childRecalced = invalidateStyleForClassChange(child, invalidationClasses, foundInvalidationSet);
+        someChildrenNeedStyleRecalc = someChildrenNeedStyleRecalc || childRecalced;
     }
     return someChildrenNeedStyleRecalc;
 }
 
 bool RuleFeatureSet::invalidateStyleForClassChange(Element* element, Vector<AtomicString>& invalidationClasses, bool foundInvalidationSet)
 {
     int oldSize = invalidationClasses.size();
     if (element->needsStyleInvalidation()) {
         if (InvalidationList* invalidationList = m_pendingInvalidationMap.get(element)) {
             foundInvalidationSet = true;
@@ skipping 32 matching lines @@
 
     if (thisElementNeedsStyleRecalc)
         element->setNeedsStyleRecalc(LocalStyleChange);
 
     invalidationClasses.remove(oldSize, invalidationClasses.size() - oldSize);
     element->clearChildNeedsStyleInvalidation();
     return thisElementNeedsStyleRecalc;
 }
 
 } // namespace WebCore