Add support for DOM4's XMLDocument interface

Source/core/inspector/InspectorDOMAgent.cpp

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Google Inc. All rights reserved.
  * Copyright (C) 2009 Joseph Pecoraro
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
@@ skipping 793 matching lines @@
         DOMPatchSupport domPatchSupport(m_domEditor.get(), *m_document.get());
         domPatchSupport.patchDocument(outerHTML);
         return;
     }
 
     Node* node = assertEditableNode(errorString, nodeId);
     if (!node)
         return;
 
     Document* document = node->isDocumentNode() ? toDocument(node) : node->ownerDocument();
-    if (!document || (!document->isHTMLDocument() && !document->isXHTMLDocument() && !document->isSVGDocument())) {
+    if (!document || (!document->isHTMLDocument() && !document->isXMLDocument())) {
         *errorString = "Not an HTML/XML document";
         return;
     }
 
     Node* newNode = 0;
     if (!m_domEditor->setOuterHTML(node, outerHTML, &newNode, errorString))
         return;
 
     if (!newNode) {
         // The only child node has been deleted.
@@ skipping 1203 matching lines @@
     if (!m_documentNodeToIdMap.contains(m_document)) {
         RefPtr<TypeBuilder::DOM::Node> root;
         getDocument(errorString, root);
         return errorString->isEmpty();
     }
     return true;
 }
 
 } // namespace WebCore