Make sure the rootNode of a LiveNodeListBase is always a ContainerNode

Source/core/dom/NameNodeList.h

 /*
  * 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, 2007m 2008 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 15 matching lines @@
 
 #include "core/dom/LiveNodeList.h"
 #include "wtf/Forward.h"
 #include "wtf/text/AtomicString.h"
 
 namespace WebCore {
 
 // NodeList which lists all Nodes in a Element with a given "name" attribute
 class NameNodeList FINAL : public LiveNodeList {
 public:
-    static PassRefPtr<NameNodeList> create(PassRefPtr<Node> rootNode, CollectionType type, const AtomicString& name)
+    static PassRefPtr<NameNodeList> create(PassRefPtr<ContainerNode> rootNode, CollectionType type, const AtomicString& name)
     {
         ASSERT_UNUSED(type, type == NameNodeListType);
         return adoptRef(new NameNodeList(rootNode, name));
     }
 
     virtual ~NameNodeList();
 
 private:
-    NameNodeList(PassRefPtr<Node> rootNode, const AtomicString& name);
+    NameNodeList(PassRefPtr<ContainerNode> rootNode, const AtomicString& name);
 
     virtual bool nodeMatches(const Element&) const OVERRIDE;
 
     AtomicString m_name;
 };
 
 } // namespace WebCore
 
 #endif // NameNodeList_h