Revert of Revert of Add a WorkerScheduler and a WebThreadImplForWorker

content/child/scheduler/webthread_impl_for_worker_scheduler.h

Index: content/child/scheduler/webthread_impl_for_worker_scheduler.h
diff --git a/content/child/scheduler/webthread_impl_for_worker_scheduler.h b/content/child/scheduler/webthread_impl_for_worker_scheduler.h
new file mode 100644
index 0000000000000000000000000000000000000000..25362d78ce87ba527b25d552242b374d33b3601e
--- /dev/null
+++ b/content/child/scheduler/webthread_impl_for_worker_scheduler.h
@@ -0,0 +1,50 @@
+// Copyright 2015 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.
+
+#ifndef CONTENT_CHILD_SCHEDULER_WEBTHREAD_IMPL_FOR_WORKER_SCHEDULER_H_
+#define CONTENT_CHILD_SCHEDULER_WEBTHREAD_IMPL_FOR_WORKER_SCHEDULER_H_
+
+#include "content/child/scheduler/task_queue_manager.h"
+#include "content/child/webthread_base.h"
+
+namespace base {
+class WaitableEvent;
+};
+
+namespace content {
+
+class SingleThreadIdleTaskRunner;
+class WorkerScheduler;
+
+class CONTENT_EXPORT WebThreadImplForWorkerScheduler : public WebThreadBase {
+ public:
+  explicit WebThreadImplForWorkerScheduler(const char* name);
+  virtual ~WebThreadImplForWorkerScheduler();
+
+  // blink::WebThread implementation.
+  blink::PlatformThreadId threadId() const override;
+
+  // WebThreadBase implementation.
+  base::SingleThreadTaskRunner* TaskRunner() const override;
+  SingleThreadIdleTaskRunner* IdleTaskRunner() const override;
+
+ private:
+  base::MessageLoop* MessageLoop() const override;
+  void AddTaskObserverInternal(
+      base::MessageLoop::TaskObserver* observer) override;
+  void RemoveTaskObserverInternal(
+      base::MessageLoop::TaskObserver* observer) override;
+
+  void InitOnThread(base::WaitableEvent* completion);
+  void ShutDownOnThread(base::WaitableEvent* completion);
+
+  scoped_ptr<base::Thread> thread_;
+  scoped_ptr<WorkerScheduler> worker_scheduler_;
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
+  scoped_refptr<SingleThreadIdleTaskRunner> idle_task_runner_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_CHILD_SCHEDULER_WEBTHREAD_IMPL_FOR_WORKER_SCHEDULER_H_