Revert of Make Response::body return v8-extra based stream behind flag

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

Index: third_party/WebKit/Source/modules/fetch/Body.cpp
diff --git a/third_party/WebKit/Source/modules/fetch/Body.cpp b/third_party/WebKit/Source/modules/fetch/Body.cpp
index eadb58918aa3af3a61704ea7edd98e57d9b4183b..670ea27b1e45ca179c84449e2b08beb0cad2f913 100644
--- a/third_party/WebKit/Source/modules/fetch/Body.cpp
+++ b/third_party/WebKit/Source/modules/fetch/Body.cpp
@@ -4,6 +4,7 @@
 
 #include "modules/fetch/Body.h"
 
+#include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptPromiseResolver.h"
 #include "bindings/core/v8/ScriptState.h"
 #include "bindings/core/v8/V8ArrayBuffer.h"
@@ -13,6 +14,9 @@
 #include "core/dom/ExceptionCode.h"
 #include "core/fileapi/Blob.h"
 #include "core/frame/UseCounter.h"
+#include "core/streams/ReadableStreamController.h"
+#include "core/streams/ReadableStreamOperations.h"
+#include "core/streams/UnderlyingSourceBase.h"
 #include "modules/fetch/BodyStreamBuffer.h"
 #include "modules/fetch/FetchDataLoader.h"
 #include "public/platform/WebDataConsumerHandle.h"
@@ -100,6 +104,59 @@
     }
 };
 
+class UnderlyingSourceFromDataConsumerHandle final : public UnderlyingSourceBase, public WebDataConsumerHandle::Client {
+    EAGERLY_FINALIZE();
+    DECLARE_EAGER_FINALIZATION_OPERATOR_NEW();
+public:
+    UnderlyingSourceFromDataConsumerHandle(ScriptState* scriptState, PassOwnPtr<WebDataConsumerHandle> handle)
+        : UnderlyingSourceBase(scriptState)
+        , m_scriptState(scriptState)
+        , m_reader(handle->obtainReader(this))
+    {
+    }
+
+    ScriptPromise pull(ScriptState* scriptState) override
+    {
+        didGetReadable();
+        return ScriptPromise::castUndefined(scriptState);
+    }
+
+    ScriptPromise cancel(ScriptState* scriptState, ScriptValue reason) override
+    {
+        m_reader = nullptr;
+        return ScriptPromise::castUndefined(scriptState);
+    }
+
+    void didGetReadable() override
+    {
+        while (controller()->desiredSize() > 0) {
+            size_t available = 0;
+            const void* buffer = nullptr;
+            WebDataConsumerHandle::Result result = m_reader->beginRead(&buffer, WebDataConsumerHandle::FlagNone, &available);
+            if (result == WebDataConsumerHandle::Ok) {
+                RefPtr<ArrayBuffer> arrayBuffer = ArrayBuffer::create(available, 1);
+                memcpy(arrayBuffer->data(), buffer, available);
+                m_reader->endRead(available);
+                controller()->enqueue(DOMUint8Array::create(arrayBuffer.release(), 0, available));
+            } else if (result == WebDataConsumerHandle::ShouldWait) {
+                break;
+            } else if (result == WebDataConsumerHandle::Done) {
+                m_reader = nullptr;
+                controller()->close();
+                break;
+            } else {
+                m_reader = nullptr;
+                controller()->error(V8ThrowException::createTypeError(m_scriptState->isolate(), "Network error"));
+                break;
+            }
+        }
+    }
+
+private:
+    RefPtr<ScriptState> m_scriptState;
+    OwnPtr<WebDataConsumerHandle::Reader> m_reader;
+};
+
 } // namespace
 
 ScriptPromise Body::arrayBuffer(ScriptState* scriptState)
@@ -120,7 +177,7 @@
     ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
     promise = resolver->promise();
     if (bodyBuffer()) {
-        bodyBuffer()->startLoading(FetchDataLoader::createLoaderAsArrayBuffer(), new BodyArrayBufferConsumer(resolver));
+        bodyBuffer()->startLoading(scriptState->getExecutionContext(), FetchDataLoader::createLoaderAsArrayBuffer(), new BodyArrayBufferConsumer(resolver));
     } else {
         resolver->resolve(DOMArrayBuffer::create(0u, 1));
     }
@@ -140,7 +197,7 @@
     ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
     promise = resolver->promise();
     if (bodyBuffer()) {
-        bodyBuffer()->startLoading(FetchDataLoader::createLoaderAsBlobHandle(mimeType()), new BodyBlobConsumer(resolver));
+        bodyBuffer()->startLoading(scriptState->getExecutionContext(), FetchDataLoader::createLoaderAsBlobHandle(mimeType()), new BodyBlobConsumer(resolver));
     } else {
         OwnPtr<BlobData> blobData = BlobData::create();
         blobData->setContentType(mimeType());
@@ -163,7 +220,7 @@
     ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
     promise = resolver->promise();
     if (bodyBuffer()) {
-        bodyBuffer()->startLoading(FetchDataLoader::createLoaderAsString(), new BodyJsonConsumer(resolver));
+        bodyBuffer()->startLoading(scriptState->getExecutionContext(), FetchDataLoader::createLoaderAsString(), new BodyJsonConsumer(resolver));
     } else {
         resolver->reject(V8ThrowException::createSyntaxError(scriptState->isolate(), "Unexpected end of input"));
     }
@@ -183,21 +240,32 @@
     ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
     promise = resolver->promise();
     if (bodyBuffer()) {
-        bodyBuffer()->startLoading(FetchDataLoader::createLoaderAsString(), new BodyTextConsumer(resolver));
+        bodyBuffer()->startLoading(scriptState->getExecutionContext(), FetchDataLoader::createLoaderAsString(), new BodyTextConsumer(resolver));
     } else {
         resolver->resolve(String());
     }
     return promise;
 }
 
-ScriptValue Body::bodyWithUseCounter(ScriptState* scriptState)
+ReadableByteStream* Body::body()
+{
+    return bodyBuffer() ? bodyBuffer()->stream() : nullptr;
+}
+
+ReadableByteStream* Body::bodyWithUseCounter()
 {
     UseCounter::count(getExecutionContext(), UseCounter::FetchBodyStream);
-    if (!bodyBuffer())
-        return ScriptValue::createNull(scriptState);
-    ScriptValue stream = bodyBuffer()->stream();
-    ASSERT(stream.getScriptState() == scriptState);
-    return stream;
+    return body();
+}
+
+ScriptValue Body::v8ExtraStreamBody(ScriptState* scriptState)
+{
+    if (bodyUsed() || isBodyLocked() || !bodyBuffer())
+        return ScriptValue(scriptState, v8::Undefined(scriptState->isolate()));
+    OwnPtr<FetchDataConsumerHandle> handle = bodyBuffer()->releaseHandle(scriptState->getExecutionContext());
+    return ReadableStreamOperations::createReadableStream(scriptState,
+        new UnderlyingSourceFromDataConsumerHandle(scriptState, handle.release()),
+        ScriptValue(scriptState, v8::Undefined(scriptState->isolate())));
 }
 
 bool Body::bodyUsed()