Migrate SchedulerWorkerPoolImpl to AtomicFlag

base/task_scheduler/scheduler_worker_pool_impl.h

 // 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.
 
 #ifndef BASE_TASK_SCHEDULER_SCHEDULER_WORKER_POOL_IMPL_H_
 #define BASE_TASK_SCHEDULER_SCHEDULER_WORKER_POOL_IMPL_H_
 
 #include <stddef.h>
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/base_export.h"
 #include "base/callback.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/strings/string_piece.h"
+#include "base/synchronization/atomic_flag.h"
 #include "base/synchronization/condition_variable.h"
 #include "base/task_runner.h"
 #include "base/task_scheduler/priority_queue.h"
 #include "base/task_scheduler/scheduler_lock.h"
 #include "base/task_scheduler/scheduler_worker.h"
 #include "base/task_scheduler/scheduler_worker_pool.h"
 #include "base/task_scheduler/scheduler_worker_pool_params.h"
 #include "base/task_scheduler/scheduler_worker_stack.h"
 #include "base/task_scheduler/sequence.h"
 #include "base/task_scheduler/task.h"
@@ skipping 124 matching lines @@
 
   // Stack of idle workers.
   SchedulerWorkerStack idle_workers_stack_;
 
   // Signaled when all workers become idle.
   std::unique_ptr<ConditionVariable> idle_workers_stack_cv_for_testing_;
 
   // Signaled once JoinForTesting() has returned.
   WaitableEvent join_for_testing_returned_;
 
-  // Synchronizes access to |worker_detachment_allowed_|.
-  SchedulerLock worker_detachment_allowed_lock_;
-
-  // Indicates to the delegates that workers are permitted to detach their
+  // Indicates to the delegates that workers are not permitted to detach their
   // threads.
-  bool worker_detachment_allowed_ = true;
+  AtomicFlag worker_detachment_disallowed_;
 
 #if DCHECK_IS_ON()
   // Signaled when all workers have been created.
   WaitableEvent workers_created_;
 #endif
 
   TaskTracker* const task_tracker_;
   DelayedTaskManager* const delayed_task_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(SchedulerWorkerPoolImpl);
 };
 
 }  // namespace internal
 }  // namespace base
 
 #endif  // BASE_TASK_SCHEDULER_SCHEDULER_WORKER_POOL_IMPL_H_