scheduler: Move the Blink scheduler into Blink

components/scheduler/base/enqueue_order.h

-// 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 COMPONENTS_SCHEDULER_BASE_ENQUEUE_ORDER_H_
-#define COMPONENTS_SCHEDULER_BASE_ENQUEUE_ORDER_H_
-
-#include <stdint.h>
-
-#include "base/synchronization/lock.h"
-
-namespace scheduler {
-namespace internal {
-
-using EnqueueOrder = uint64_t;
-
-class EnqueueOrderGenerator {
- public:
-  EnqueueOrderGenerator();
-  ~EnqueueOrderGenerator();
-
-  EnqueueOrder GenerateNext();
-
- private:
-  base::Lock lock_;
-  EnqueueOrder enqueue_order_;
-};
-
-}  // namespace internal
-}  // namespace scheduler
-
-#endif  // COMPONENTS_SCHEDULER_BASE_ENQUEUE_ORDER_H_