Support embedded created Response objects in ServiceWorker.

public/platform/WebServiceWorkerResponse.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef WebServiceWorkerResponse_h
 #define WebServiceWorkerResponse_h
 
 #include "WebCommon.h"
 #include "public/platform/WebPrivatePtr.h"
 #include "public/platform/WebString.h"
 #include "public/platform/WebURL.h"
 #include "public/platform/WebVector.h"
 
 #if INSIDE_BLINK
 #include "wtf/Forward.h"
 #include "wtf/HashMap.h"
 #include "wtf/text/StringHash.h"
 #endif
 
 namespace blink {
 
 class BlobDataHandle;
+class WebHTTPHeaderVisitor;
 class WebServiceWorkerResponsePrivate;
 
 // Represents a response to a fetch operation. ServiceWorker uses this to
 // respond to a FetchEvent dispatched by the browser. The plan is for the Cache
 // and fetch() API to also use it.
 class BLINK_PLATFORM_EXPORT WebServiceWorkerResponse {
 public:
     ~WebServiceWorkerResponse() { reset(); }
     WebServiceWorkerResponse();
+    WebServiceWorkerResponse(const WebServiceWorkerResponse& other) { assign(other); }
     WebServiceWorkerResponse& operator=(const WebServiceWorkerResponse& other)
     {
         assign(other);
         return *this;
     }
 
     void reset();
     void assign(const WebServiceWorkerResponse&);
 
     void setURL(const WebURL&);
     WebURL url() const;
 
     void setStatus(unsigned short);
     unsigned short status() const;
 
     void setStatusText(const WebString&);
     WebString statusText() const;
 
     void setHeader(const WebString& key, const WebString& value);
     WebVector<WebString> getHeaderKeys() const;
     WebString getHeader(const WebString& key) const;
+    void visitHTTPHeaderFields(WebHTTPHeaderVisitor*) const;
 
     WebString blobUUID() const;
 
 #if INSIDE_BLINK
     void setHeaders(const HashMap<String, String>&);
     const HashMap<String, String>& headers() const;
 
     void setBlobDataHandle(PassRefPtr<BlobDataHandle>);
     PassRefPtr<BlobDataHandle> blobDataHandle() const;
 #endif
 
 private:
     WebPrivatePtr<WebServiceWorkerResponsePrivate> m_private;
 };
 
 } // namespace blink
 
 #endif // WebServiceWorkerResponse_h