(WIP) Worker: Merge ParentFrameTaskRunners into TaskRunnerHelper

third_party/WebKit/Source/core/workers/ParentFrameTaskRunners.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/ParentFrameTaskRunners.h"
-
-#include "core/dom/Document.h"
-#include "core/frame/LocalFrame.h"
-#include "public/platform/Platform.h"
-#include "wtf/Assertions.h"
-#include "wtf/ThreadingPrimitives.h"
-
-namespace blink {
-
-ParentFrameTaskRunners::ParentFrameTaskRunners(LocalFrame* frame)
-    : ContextLifecycleObserver(frame ? frame->document() : nullptr) {
-  if (frame && frame->document())
-    DCHECK(frame->document()->isContextThread());
-
-  // For now we only support very limited task types.
-  for (auto type : {TaskType::UnspecedTimer, TaskType::UnspecedLoading,
-                    TaskType::Networking, TaskType::PostedMessage,
-                    TaskType::CanvasBlobSerialization, TaskType::Unthrottled}) {
-    m_taskRunners.insert(type, TaskRunnerHelper::get(type, frame));
-  }
-}
-
-RefPtr<WebTaskRunner> ParentFrameTaskRunners::get(TaskType type) {
-  MutexLocker lock(m_taskRunnersMutex);
-  return m_taskRunners.at(type);
-}
-
-DEFINE_TRACE(ParentFrameTaskRunners) {
-  ContextLifecycleObserver::trace(visitor);
-}
-
-void ParentFrameTaskRunners::contextDestroyed(ExecutionContext*) {
-  MutexLocker lock(m_taskRunnersMutex);
-  for (auto& entry : m_taskRunners)
-    entry.value = Platform::current()->currentThread()->getWebTaskRunner();
-}
-
-}  // namespace blink