Implement File constructor.

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 666 matching lines @@
             if (!blobType.isEmpty() && isValidContentType(blobType))
                 setRequestHeaderInternal("Content-Type", blobType);
             else {
                 // From FileAPI spec, whenever media type cannot be determined, empty string must be returned.
                 setRequestHeaderInternal("Content-Type", "");
             }
         }
 
         // FIXME: add support for uploading bundles.
         m_requestEntityBody = FormData::create();
-        if (body->isFile())
+        if (body->hasBackingFile())
             m_requestEntityBody->appendFile(toFile(body)->path());
         else
             m_requestEntityBody->appendBlob(body->uuid(), body->blobDataHandle());
     }
 
     createRequest(es);
 }
 
 void XMLHttpRequest::send(DOMFormData* body, ExceptionState& es)
 {
@@ skipping 668 matching lines @@
 {
     return EventTargetNames::XMLHttpRequest;
 }
 
 ExecutionContext* XMLHttpRequest::executionContext() const
 {
     return ActiveDOMObject::executionContext();
 }
 
 } // namespace WebCore