[Fetch API] Remove DrainingBuffer.

Source/modules/fetch/FetchRequestData.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 FetchRequestData_h
 #define FetchRequestData_h
 
 #include "platform/heap/Handle.h"
 #include "platform/weborigin/KURL.h"
 #include "platform/weborigin/Referrer.h"
@@ skipping 78 matching lines @@
     // Call Request::refreshBody() after calling setBuffer().
     void setBuffer(BodyStreamBuffer* buffer) { m_buffer = buffer; }
     String mimeType() const { return m_mimeType; }
     void setMIMEType(const String& type) { m_mimeType = type; }
 
     DECLARE_TRACE();
 
 private:
     FetchRequestData();
 
+    FetchRequestData* cloneExceptBody();
+
     AtomicString m_method;
     KURL m_url;
     Member<FetchHeaderList> m_headerList;
     bool m_unsafeRequestFlag;
     // FIXME: Support m_skipServiceWorkerFlag;
     WebURLRequest::RequestContext m_context;
     RefPtr<SecurityOrigin> m_origin;
     // FIXME: Support m_forceOriginHeaderFlag;
     bool m_sameOriginDataURLFlag;
     Referrer m_referrer;
     // FIXME: Support m_authenticationFlag;
     // FIXME: Support m_synchronousFlag;
     WebURLRequest::FetchRequestMode m_mode;
     WebURLRequest::FetchCredentialsMode m_credentials;
     // FIXME: Support m_useURLCredentialsFlag;
     // FIXME: Support m_manualRedirectFlag;
     // FIXME: Support m_redirectCount;
     Tainting m_responseTainting;
     Member<BodyStreamBuffer> m_buffer;
     String m_mimeType;
 };
 
 } // namespace blink
 
 #endif // FetchRequestData_h