Introduce ThreadableLoadingContext: make threaded loading code one step away from Document

third_party/WebKit/Source/core/workers/ThreadedMessagingProxyBase.cpp

 // Copyright 2016 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 "core/workers/ThreadedMessagingProxyBase.h"
 
 #include "bindings/core/v8/SourceLocation.h"
 #include "core/dom/Document.h"
-#include "core/dom/ExecutionContextTask.h"
 #include "core/frame/Deprecation.h"
 #include "core/loader/DocumentLoader.h"
+#include "core/loader/ThreadableLoadingContext.h"
 #include "core/workers/WorkerInspectorProxy.h"
 #include "core/workers/WorkerThreadStartupData.h"
 #include "wtf/CurrentTime.h"
 
 namespace blink {
 
 namespace {
 
 static int s_liveMessagingProxyCount = 0;
 
@@ skipping 48 matching lines @@
   m_workerThread->postTask(location, std::move(task));
 }
 
 void ThreadedMessagingProxyBase::postTaskToLoader(
     const WebTraceLocation& location,
     std::unique_ptr<WTF::CrossThreadClosure> task) {
   m_parentFrameTaskRunners->get(TaskType::Networking)
       ->postTask(BLINK_FROM_HERE, std::move(task));
 }
 
-ExecutionContext* ThreadedMessagingProxyBase::getLoaderExecutionContext() {
+ThreadableLoadingContext*
+ThreadedMessagingProxyBase::getThreadableLoadingContext() {
   DCHECK(isParentContextThread());
-  return getExecutionContext();
+  if (!m_loadingContext) {
+    m_loadingContext =
+        ThreadableLoadingContext::create(*toDocument(m_executionContext));
+  }
+  return m_loadingContext;
 }
 
 void ThreadedMessagingProxyBase::countFeature(UseCounter::Feature feature) {
   DCHECK(isParentContextThread());
   UseCounter::count(m_executionContext, feature);
 }
 
 void ThreadedMessagingProxyBase::countDeprecation(UseCounter::Feature feature) {
   DCHECK(isParentContextThread());
   Deprecation::countDeprecation(m_executionContext, feature);
@@ skipping 72 matching lines @@
 }
 
 bool ThreadedMessagingProxyBase::isParentContextThread() const {
   // TODO(nhiroki): Nested worker is not supported yet, so the parent context
   // thread should be equal to the main thread (http://crbug.com/31666).
   DCHECK(m_executionContext->isDocument());
   return isMainThread();
 }
 
 }  // namespace blink