Stop passing the root node to node lists traversal functions

Source/core/html/HTMLCollection.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2014 Samsung Electronics. 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 288 matching lines @@
         || element.hasLocalName(formTag)
         || element.hasLocalName(frameTag)
         || element.hasLocalName(framesetTag)
         || element.hasLocalName(iframeTag)
         || element.hasLocalName(imgTag)
         || element.hasLocalName(inputTag)
         || element.hasLocalName(objectTag)
         || element.hasLocalName(selectTag);
 }
 
-inline Element* firstMatchingChildElement(const HTMLCollection& nodeList, const ContainerNode& root)
+inline Element* firstMatchingChildElement(const HTMLCollection& nodeList)
 {
-    Element* element = ElementTraversal::firstChild(root);
+    Element* element = ElementTraversal::firstChild(nodeList.rootNode());
     while (element && !isMatchingElement(nodeList, *element))
         element = ElementTraversal::nextSibling(*element);
     return element;
 }
 
 inline Element* nextMatchingChildElement(const HTMLCollection& nodeList, Element& current)
 {
     Element* next = &current;
     do {
         next = ElementTraversal::nextSibling(*next);
     } while (next && !isMatchingElement(nodeList, *next));
     return next;
 }
 
-Element* HTMLCollection::traverseToFirstElement(const ContainerNode& root) const
+Element* HTMLCollection::traverseToFirstElement() const
 {
     switch (type()) {
     case HTMLTagCollectionType:
-        return firstMatchingElement(static_cast<const HTMLTagCollection&>(*this), root);
+        return firstMatchingElement(static_cast<const HTMLTagCollection&>(*this));
     case ClassCollectionType:
-        return firstMatchingElement(static_cast<const ClassCollection&>(*this), root);
+        return firstMatchingElement(static_cast<const ClassCollection&>(*this));
     default:
         if (overridesItemAfter())
             return virtualItemAfter(0);
         if (shouldOnlyIncludeDirectChildren())
-            return firstMatchingChildElement(*this, root);
-        return firstMatchingElement(*this, root);
+            return firstMatchingChildElement(*this);
+        return firstMatchingElement(*this);
     }
 }
 
-inline Element* HTMLCollection::traverseNextElement(Element& previous, const ContainerNode& root) const
+inline Element* HTMLCollection::traverseNextElement(Element& previous) const
 {
     if (overridesItemAfter())
         return virtualItemAfter(&previous);
     if (shouldOnlyIncludeDirectChildren())
         return nextMatchingChildElement(*this, previous);
-    return nextMatchingElement(*this, previous, root);
+    return nextMatchingElement(*this, previous);
 }
 
-Element* HTMLCollection::traverseForwardToOffset(unsigned offset, Element& currentElement, unsigned& currentOffset, const ContainerNode& root) const
+Element* HTMLCollection::traverseForwardToOffset(unsigned offset, Element& currentElement, unsigned& currentOffset) const
 {
     ASSERT(currentOffset < offset);
     switch (type()) {
     case HTMLTagCollectionType:
-        return traverseMatchingElementsForwardToOffset(static_cast<const HTMLTagCollection&>(*this), offset, currentElement, currentOffset, root);
+        return traverseMatchingElementsForwardToOffset(static_cast<const HTMLTagCollection&>(*this), offset, currentElement, currentOffset);
     case ClassCollectionType:
-        return traverseMatchingElementsForwardToOffset(static_cast<const ClassCollection&>(*this), offset, currentElement, currentOffset, root);
+        return traverseMatchingElementsForwardToOffset(static_cast<const ClassCollection&>(*this), offset, currentElement, currentOffset);
     default:
         if (overridesItemAfter()) {
             Element* next = &currentElement;
             while ((next = virtualItemAfter(next))) {
                 if (++currentOffset == offset)
                     return next;
             }
             return 0;
         }
         if (shouldOnlyIncludeDirectChildren()) {
             Element* next = &currentElement;
             while ((next = nextMatchingChildElement(*this, *next))) {
                 if (++currentOffset == offset)
                     return next;
             }
             return 0;
         }
-        return traverseMatchingElementsForwardToOffset(*this, offset, currentElement, currentOffset, root);
+        return traverseMatchingElementsForwardToOffset(*this, offset, currentElement, currentOffset);
     }
 }
 
 Element* HTMLCollection::namedItem(const AtomicString& name) const
 {
     // http://msdn.microsoft.com/workshop/author/dhtml/reference/methods/nameditem.asp
     // This method first searches for an object with a matching id
     // attribute. If a match is not found, the method then searches for an
     // object with a matching name attribute, but only on those elements
     // that are allowed a name attribute.
@@ skipping 20 matching lines @@
 {
     // As per the specification (http://dom.spec.whatwg.org/#htmlcollection):
     // The supported property names are the values from the list returned by these steps:
     // 1. Let result be an empty list.
     // 2. For each element represented by the collection, in tree order, run these substeps:
     //   1. If element has an ID which is neither the empty string nor is in result, append element's ID to result.
     //   2. If element is in the HTML namespace and has a name attribute whose value is neither the empty string
     //      nor is in result, append element's name attribute value to result.
     // 3. Return result.
     HashSet<AtomicString> existingNames;
-    ContainerNode& root = rootNode();
-    for (Element* element = traverseToFirstElement(root); element; element = traverseNextElement(*element, root)) {
+    for (Element* element = traverseToFirstElement(); element; element = traverseNextElement(*element)) {
         const AtomicString& idAttribute = element->getIdAttribute();
         if (!idAttribute.isEmpty()) {
             HashSet<AtomicString>::AddResult addResult = existingNames.add(idAttribute);
             if (addResult.isNewEntry)
                 names.append(idAttribute);
         }
         if (!element->isHTMLElement())
             continue;
         const AtomicString& nameAttribute = element->getNameAttribute();
         if (!nameAttribute.isEmpty() && (type() != DocAll || nameShouldBeVisibleInDocumentAll(toHTMLElement(*element)))) {
             HashSet<AtomicString>::AddResult addResult = existingNames.add(nameAttribute);
             if (addResult.isNewEntry)
                 names.append(nameAttribute);
         }
     }
 }
 
 void HTMLCollection::namedPropertyEnumerator(Vector<String>& names, ExceptionState&)
 {
     supportedPropertyNames(names);
 }
 
 void HTMLCollection::updateIdNameCache() const
 {
     if (hasValidIdNameCache())
         return;
 
     NamedItemCache& cache = createNamedItemCache();
-    ContainerNode& root = rootNode();
-    for (Element* element = traverseToFirstElement(root); element; element = traverseNextElement(*element, root)) {
+    for (Element* element = traverseToFirstElement(); element; element = traverseNextElement(*element)) {
         const AtomicString& idAttrVal = element->getIdAttribute();
         if (!idAttrVal.isEmpty())
             cache.addElementWithId(idAttrVal, element);
         if (!element->isHTMLElement())
             continue;
         const AtomicString& nameAttrVal = element->getNameAttribute();
         if (!nameAttrVal.isEmpty() && idAttrVal != nameAttrVal && (type() != DocAll || nameShouldBeVisibleInDocumentAll(toHTMLElement(*element))))
             cache.addElementWithName(nameAttrVal, element);
     }
 }
@@ skipping 11 matching lines @@
     Vector<Element*>* nameResults = cache.getElementsByName(name);
 
     for (unsigned i = 0; idResults && i < idResults->size(); ++i)
         result.append(idResults->at(i));
 
     for (unsigned i = 0; nameResults && i < nameResults->size(); ++i)
         result.append(nameResults->at(i));
 }
 
 } // namespace WebCore