TaskScheduler [11] Support ExecutionMode::SINGLE_THREADED.

base/task_scheduler/delayed_task_manager.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_DELAYED_TASK_MANAGER_H_
 #define BASE_TASK_SCHEDULER_DELAYED_TASK_MANAGER_H_
 
 #include <stdint.h>
 
 #include <memory>
 #include <queue>
 #include <vector>
 
 #include "base/base_export.h"
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/task_scheduler/scheduler_lock.h"
 #include "base/task_scheduler/sequence.h"
 #include "base/task_scheduler/task.h"
 #include "base/time/time.h"
 
 namespace base {
 namespace internal {
 
 class SchedulerThreadPool;
+class SchedulerWorkerThread;
 
 // A DelayedTaskManager holds delayed Tasks until they become ripe for
-// execution. When they become ripe for execution, it posts them to their
-// associated Sequence and SchedulerThreadPool. This class is thread-safe.
+// execution. This class is thread-safe.
 class BASE_EXPORT DelayedTaskManager {
  public:
   // |on_delayed_run_time_updated| is invoked when the delayed run time is
   // updated as a result of adding a delayed task to the manager.
   explicit DelayedTaskManager(const Closure& on_delayed_run_time_updated);
   ~DelayedTaskManager();
 
   // Adds |task| to a queue of delayed tasks. The task will be posted to
-  // |thread_pool| as part of |sequence| the first time that PostReadyTasks() is
-  // called while Now() is passed |task->delayed_run_time|.
+  // |thread_pool| with |sequence| and |worker_thread| the first time that
+  // PostReadyTasks() is called while Now() is passed |task->delayed_run_time|.
+  // |worker_thread| is a SchedulerWorkerThread owned by |thread_pool| or
+  // nullptr.
   //
-  // TODO(robliao): Find a concrete way to manage |thread_pool|'s memory. It is
-  // never deleted in production, but it is better not to spread this assumption
-  // throughout the scheduler.
+  // TODO(robliao): Find a concrete way to manage the memory of |worker_thread|
+  // and |thread_pool|. These objects are never deleted in production, but it is
+  // better not to spread this assumption throughout the scheduler.
   void AddDelayedTask(std::unique_ptr<Task> task,
                       scoped_refptr<Sequence> sequence,
+                      SchedulerWorkerThread* worker_thread,
                       SchedulerThreadPool* thread_pool);
 
   // Posts delayed tasks that are ripe for execution.
   // TODO(robliao): Call this from a service thread.
   void PostReadyTasks();
 
   // Returns the next time at which a delayed task will become ripe for
   // execution, or a null TimeTicks if there are no pending delayed tasks.
   TimeTicks GetDelayedRunTime() const;
 
@@ skipping 21 matching lines @@
   // The index to assign to the next delayed task added to the manager.
   uint64_t delayed_task_index_ = 0;
 
   DISALLOW_COPY_AND_ASSIGN(DelayedTaskManager);
 };
 
 }  // namespace internal
 }  // namespace base
 
 #endif  // BASE_TASK_SCHEDULER_DELAYED_TASK_MANAGER_H_