Have XMLHttpRequest.responseXML return an XMLDocument

Source/core/xml/XMLHttpRequest.cpp

 /*
  *  Copyright (C) 2004, 2006, 2008 Apple Inc. All rights reserved.
  *  Copyright (C) 2005-2007 Alexey Proskuryakov <ap@webkit.org>
  *  Copyright (C) 2007, 2008 Julien Chaffraix <jchaffraix@webkit.org>
  *  Copyright (C) 2008, 2011 Google Inc. All rights reserved.
  *  Copyright (C) 2012 Intel Corporation
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Lesser General Public
  *  License as published by the Free Software Foundation; either
@@ skipping 11 matching lines @@
 
 #include "config.h"
 #include "core/xml/XMLHttpRequest.h"
 
 #include "FetchInitiatorTypeNames.h"
 #include "RuntimeEnabledFeatures.h"
 #include "bindings/v8/ExceptionState.h"
 #include "core/dom/ContextFeatures.h"
 #include "core/dom/DOMImplementation.h"
 #include "core/dom/ExceptionCode.h"
+#include "core/dom/XMLDocument.h"
 #include "core/editing/markup.h"
 #include "core/events/Event.h"
 #include "core/fetch/CrossOriginAccessControl.h"
 #include "core/fileapi/Blob.h"
 #include "core/fileapi/File.h"
 #include "core/fileapi/Stream.h"
 #include "core/frame/csp/ContentSecurityPolicy.h"
 #include "core/html/DOMFormData.h"
 #include "core/html/HTMLDocument.h"
 #include "core/html/parser/TextResourceDecoder.h"
@@ skipping 205 matching lines @@
         // If it is text/html, then the responseType of "document" must have been supplied explicitly.
         if ((m_response.isHTTP() && !responseIsXML() && !isHTML)
             || (isHTML && m_responseTypeCode == ResponseTypeDefault)
             || executionContext()->isWorkerGlobalScope()) {
             m_responseDocument = nullptr;
         } else {
             DocumentInit init = DocumentInit::fromContext(document()->contextDocument(), m_url);
             if (isHTML)
                 m_responseDocument = HTMLDocument::create(init);
             else
-                m_responseDocument = Document::create(init);
+                m_responseDocument = XMLDocument::create(init);
             // FIXME: Set Last-Modified.
             m_responseDocument->setContent(m_responseText.flattenToString());
             m_responseDocument->setSecurityOrigin(securityOrigin());
             m_responseDocument->setContextFeatures(document()->contextFeatures());
             if (!m_responseDocument->wellFormed())
                 m_responseDocument = nullptr;
         }
         m_createdDocument = true;
     }
 
@@ skipping 1124 matching lines @@
     return ActiveDOMObject::executionContext();
 }
 
 void XMLHttpRequest::trace(Visitor* visitor)
 {
     visitor->trace(m_responseBlob);
     visitor->trace(m_responseStream);
 }
 
 } // namespace WebCore