Pass rootNode by reference when constructing node lists / collections

Source/core/html/HTMLCollection.h

 /*
  * 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 22 matching lines @@
 
 namespace WebCore {
 
 class HTMLCollection : public ScriptWrappable, public RefCounted<HTMLCollection>, public LiveNodeListBase {
 public:
     enum ItemAfterOverrideType {
         OverridesItemAfter,
         DoesNotOverrideItemAfter,
     };
 
-    static PassRefPtr<HTMLCollection> create(ContainerNode* base, CollectionType);
+    static PassRefPtr<HTMLCollection> create(ContainerNode& base, CollectionType);
     virtual ~HTMLCollection();
     virtual void invalidateCache(Document* oldDocument = 0) const OVERRIDE;
 
     // DOM API
     unsigned length() const { return m_collectionIndexCache.nodeCount(*this); }
     Element* item(unsigned offset) const { return m_collectionIndexCache.nodeAt(*this, offset); }
     virtual Element* namedItem(const AtomicString& name) const;
     bool namedPropertyQuery(const AtomicString&, ExceptionState&);
     void namedPropertyEnumerator(Vector<String>& names, ExceptionState&);
 
     // Non-DOM API
     void namedItems(const AtomicString& name, Vector<RefPtr<Element> >&) const;
     bool isEmpty() const { return m_collectionIndexCache.isEmpty(*this); }
     bool hasExactlyOneItem() const { return m_collectionIndexCache.hasExactlyOneNode(*this); }
 
     // CollectionIndexCache API.
     bool canTraverseBackward() const { return !overridesItemAfter(); }
     Element* itemBefore(const Element* previousItem) const;
     Element* traverseToFirstElement(const ContainerNode& root) const;
     Element* traverseForwardToOffset(unsigned offset, Element& currentElement, unsigned& currentOffset, const ContainerNode& root) const;
 
 protected:
-    HTMLCollection(ContainerNode* base, CollectionType, ItemAfterOverrideType);
+    HTMLCollection(ContainerNode& base, CollectionType, ItemAfterOverrideType);
 
     bool overridesItemAfter() const { return m_overridesItemAfter; }
     virtual Element* virtualItemAfter(Element*) const;
     bool shouldOnlyIncludeDirectChildren() const { return m_shouldOnlyIncludeDirectChildren; }
     virtual void supportedPropertyNames(Vector<String>& names);
 
     virtual void updateIdNameCache() const;
     bool hasValidIdNameCache() const { return m_hasValidIdNameCache; }
     void setHasValidIdNameCache() const
     {
@@ skipping 39 matching lines @@
     mutable NodeCacheMap m_idCache;
     mutable NodeCacheMap m_nameCache;
     mutable CollectionIndexCache<HTMLCollection, Element> m_collectionIndexCache;
 
     friend class LiveNodeListBase;
 };
 
 } // namespace
 
 #endif