Make sure the rootNode of a LiveNodeListBase is always a ContainerNode

Source/core/dom/NodeList.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 13 matching lines @@
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "core/dom/NodeList.h"
 
+#include "core/dom/EmptyNodeList.h"
 #include "core/dom/LiveNodeList.h"
 #include "core/dom/Node.h"
 
 namespace WebCore {
 
 void NodeList::anonymousNamedGetter(const AtomicString& name, bool& returnValue0Enabled, RefPtr<Node>& returnValue0, bool& returnValue1Enabled, unsigned& returnValue1)
 {
     // Length property cannot be overridden.
     DEFINE_STATIC_LOCAL(const AtomicString, length, ("length", AtomicString::ConstructFromLiteral));
     if (name == length) {
         returnValue1Enabled = true;
         returnValue1 = this->length();
         return;
     }
 
     Node* result = namedItem(name);
     if (!result)
         return;
 
     returnValue0Enabled = true;
     returnValue0 = result;
 }
 
 Node* NodeList::ownerNode() const
 {
     if (isLiveNodeList())
         return static_cast<const LiveNodeList*>(this)->ownerNode();
+    if (isEmptyNodeList())
+        return static_cast<const EmptyNodeList*>(this)->ownerNode();
     return 0;
 }
 
 
 } // namespace WebCore