Introduce ExclusiveStreamReader.

Source/core/xmlhttprequest/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 142 matching lines @@
         return ScriptPromise::cast(scriptState, v8::Undefined(scriptState->isolate()));
     }
 
     // WebDataConsumerHandle::Client
     void didGetReadable() override
     {
         ASSERT(m_body);
         enqueueToStreamFromHandle();
     }
 
-    void startStream(ReadableStreamImpl<ReadableStreamChunkTypeTraits<DOMArrayBuffer> >* stream)
+    void startStream(ReadableStreamImpl<ReadableStreamChunkTypeTraits<DOMArrayBuffer>>* stream)
     {
         m_stream = stream;
         stream->didSourceStart();
     }
 
     void didReceiveData(const char* data, size_t size)
     {
         m_stream->enqueue(DOMArrayBuffer::create(data, size));
     }
 
@@ skipping 1412 matching lines @@
         m_finalResponseCharset = extractCharsetFromMediaType(m_mimeTypeOverride);
     }
 
     if (m_finalResponseCharset.isEmpty())
         m_finalResponseCharset = response.textEncodingName();
 
     if (handle) {
         ASSERT(!m_responseStream);
         ASSERT(!m_responseStreamSource);
         m_responseStreamSource = new ReadableStreamSource(this, handle);
-        m_responseStream = new ReadableStreamImpl<ReadableStreamChunkTypeTraits<DOMArrayBuffer> >(executionContext(), m_responseStreamSource);
+        m_responseStream = new ReadableStreamImpl<ReadableStreamChunkTypeTraits<DOMArrayBuffer>>(executionContext(), m_responseStreamSource);
         m_responseStreamSource->startStream(m_responseStream);
 
         // This protection seems needed to keep |this| alive after changeState
         // calling which may call event listeners.
         RefPtrWillBeRawPtr<XMLHttpRequest> protect(this);
         changeState(HEADERS_RECEIVED);
         if (m_error) {
             // We need to check for |m_error| because |changeState| may trigger
             // readystatechange, and user javascript can cause |abort()|.
             return;
@@ skipping 79 matching lines @@
             m_binaryResponseBuilder = SharedBuffer::create();
         m_binaryResponseBuilder->append(data, len);
     } else if (m_responseTypeCode == ResponseTypeLegacyStream) {
         if (!m_responseLegacyStream)
             m_responseLegacyStream = Stream::create(executionContext(), responseType());
         m_responseLegacyStream->addData(data, len);
     } else if (m_responseTypeCode == ResponseTypeStream) {
         if (!m_responseStream) {
             ASSERT(!m_responseStreamSource);
             m_responseStreamSource = new ReadableStreamSource(this, nullptr);
-            m_responseStream = new ReadableStreamImpl<ReadableStreamChunkTypeTraits<DOMArrayBuffer> >(executionContext(), m_responseStreamSource);
+            m_responseStream = new ReadableStreamImpl<ReadableStreamChunkTypeTraits<DOMArrayBuffer>>(executionContext(), m_responseStreamSource);
             m_responseStreamSource->startStream(m_responseStream);
         }
         m_responseStreamSource->didReceiveData(data, len);
     }
 
     if (m_blobLoader) {
         // In this case, the data is provided by m_blobLoader. As progress
         // events are already fired, we should return here.
         return;
     }
@@ skipping 59 matching lines @@
 bool XMLHttpRequest::hasPendingActivity() const
 {
     // Neither this object nor the JavaScript wrapper should be deleted while
     // a request is in progress because we need to keep the listeners alive,
     // and they are referenced by the JavaScript wrapper.
     // |m_loader| is non-null while request is active and ThreadableLoaderClient
     // callbacks may be called, and |m_responseDocumentParser| is non-null while
     // DocumentParserClient callbacks may be called.
     if (m_loader || m_responseDocumentParser)
         return true;
-    if (m_responseStream && (m_responseStream->state() == ReadableStream::Readable || m_responseStream->state() == ReadableStream::Waiting))
+    if (m_responseStream && m_responseStream->hasPendingActivity())
         return true;
     return false;
 }
 
 void XMLHttpRequest::contextDestroyed()
 {
     ASSERT(!m_loader);
     ActiveDOMObject::contextDestroyed();
 }
 
@@ skipping 17 matching lines @@
     visitor->trace(m_responseDocumentParser);
     visitor->trace(m_progressEventThrottle);
     visitor->trace(m_upload);
     visitor->trace(m_blobLoader);
     XMLHttpRequestEventTarget::trace(visitor);
     DocumentParserClient::trace(visitor);
     ActiveDOMObject::trace(visitor);
 }
 
 } // namespace blink