[Fetch API] Reflect spec changes of bodyUsed property

third_party/WebKit/Source/modules/fetch/Response.cpp

 // 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.
 
 #include "config.h"
 #include "modules/fetch/Response.h"
 
 #include "bindings/core/v8/Dictionary.h"
 #include "bindings/core/v8/ExceptionState.h"
 #include "core/dom/DOMArrayBuffer.h"
@@ skipping 321 matching lines @@
 }
 
 Headers* Response::headers() const
 {
     // "The headers attribute's getter must return the associated Headers object."
     return m_headers;
 }
 
 Response* Response::clone(ExceptionState& exceptionState)
 {
-    if (bodyUsed()) {
+    if (isBodyLocked() || bodyUsed()) {
         exceptionState.throwTypeError("Response body is already used");
         return nullptr;
     }
 
     FetchResponseData* response = m_response->clone(executionContext());
     Headers* headers = Headers::create(response->headerList());
     headers->setGuard(m_headers->guard());
     return new Response(executionContext(), response, headers);
 }
 
@@ skipping 30 matching lines @@
 }
 
 Response::Response(ExecutionContext* context, FetchResponseData* response, Headers* headers)
     : Body(context) , m_response(response) , m_headers(headers) {}
 
 bool Response::hasBody() const
 {
     return m_response->internalBuffer();
 }
 
+bool Response::bodyUsed()
+{
+    return internalBodyBuffer() && internalBodyBuffer()->stream()->isDisturbed();
+}
+
 String Response::mimeType() const
 {
     return m_response->mimeType();
 }
 
 String Response::internalMIMEType() const
 {
     return m_response->internalMIMEType();
 }
 
 DEFINE_TRACE(Response)
 {
     Body::trace(visitor);
     visitor->trace(m_response);
     visitor->trace(m_headers);
 }
 
 } // namespace blink