Use per-frame TaskRunner instead of thread's default in DataConsumerHandle

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

Index: third_party/WebKit/Source/modules/fetch/BodyStreamBuffer.cpp
diff --git a/third_party/WebKit/Source/modules/fetch/BodyStreamBuffer.cpp b/third_party/WebKit/Source/modules/fetch/BodyStreamBuffer.cpp
index ea9bebed928461031340a6baa041b9e68de1e88c..ea6bc8455c355e66a359ee1ebf9b71b9540e4126 100644
--- a/third_party/WebKit/Source/modules/fetch/BodyStreamBuffer.cpp
+++ b/third_party/WebKit/Source/modules/fetch/BodyStreamBuffer.cpp
@@ -10,6 +10,7 @@
 #include "core/dom/DOMArrayBuffer.h"
 #include "core/dom/DOMTypedArray.h"
 #include "core/dom/ExceptionCode.h"
+#include "core/dom/TaskRunnerHelper.h"
 #include "core/streams/ReadableStreamController.h"
 #include "core/streams/ReadableStreamOperations.h"
 #include "core/workers/WorkerGlobalScope.h"
@@ -102,7 +103,7 @@ BodyStreamBuffer::BodyStreamBuffer(ScriptState* scriptState, std::unique_ptr<Fet
     : UnderlyingSourceBase(scriptState)
     , m_scriptState(scriptState)
     , m_handle(std::move(handle))
-    , m_reader(m_handle->obtainFetchDataReader(this))
+    , m_reader(m_handle->obtainFetchDataReader(this, TaskRunnerHelper::getUnthrottledTaskRunner(scriptState)->clone()))
     , m_madeFromReadableStream(false)
 {
     if (RuntimeEnabledFeatures::responseBodyWithV8ExtraStreamEnabled()) {
@@ -215,7 +216,7 @@ void BodyStreamBuffer::startLoading(FetchDataLoader* loader, FetchDataLoader::Cl
     ASSERT(m_scriptState->contextIsValid());
     std::unique_ptr<FetchDataConsumerHandle> handle = releaseHandle();
     m_loader = loader;
-    loader->start(handle.get(), new LoaderClient(m_scriptState->getExecutionContext(), this, client));
+    loader->start(handle.get(), new LoaderClient(m_scriptState->getExecutionContext(), this, client), TaskRunnerHelper::getUnthrottledTaskRunner(m_scriptState.get())->clone());
 }
 
 void BodyStreamBuffer::tee(BodyStreamBuffer** branch1, BodyStreamBuffer** branch2)