Implement PostDelayedTaskAt for guaranteed timer ordering

components/scheduler/child/task_queue_manager.h

 // Copyright 2014 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_RENDERER_SCHEDULER_TASK_QUEUE_MANAGER_H_
 #define CONTENT_RENDERER_SCHEDULER_TASK_QUEUE_MANAGER_H_
 
 #include "base/atomic_sequence_num.h"
 #include "base/debug/task_annotator.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/pending_task.h"
-#include "base/single_thread_task_runner.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread_checker.h"
 #include "components/scheduler/child/task_queue_selector.h"
 #include "components/scheduler/scheduler_export.h"
 
 namespace base {
 namespace trace_event {
 class ConvertableToTraceFormat;
 class TracedValue;
 }
 class TickClock;
 }
 
 namespace scheduler {
+class TaskQueue;
 namespace internal {
 class LazyNow;
-class TaskQueue;
+class TaskQueueImpl;
 }
 class NestableSingleThreadTaskRunner;
 class TaskQueueSelector;
 
 // The task queue manager provides N task queues and a selector interface for
 // choosing which task queue to service next. Each task queue consists of two
 // sub queues:
 //
 // 1. Incoming task queue. Tasks that are posted get immediately appended here.
 //    When a task is appended into an empty incoming queue, the task manager
@@ skipping 58 matching lines @@
   // lifetime (statics or literals). They may not include " chars.
   TaskQueueManager(
       size_t task_queue_count,
       scoped_refptr<NestableSingleThreadTaskRunner> main_task_runner,
       TaskQueueSelector* selector,
       const char* disabled_by_default_tracing_category,
       const char* disabled_by_default_verbose_tracing_category);
   ~TaskQueueManager() override;
 
   // Returns the task runner which targets the queue selected by |queue_index|.
-  scoped_refptr<base::SingleThreadTaskRunner> TaskRunnerForQueue(
-      size_t queue_index) const;
+  scoped_refptr<TaskQueue> TaskRunnerForQueue(size_t queue_index) const;
 
   // Sets the pump policy for the |queue_index| to |pump_policy|. By
   // default queues are created with AUTO_PUMP_POLICY.
   void SetPumpPolicy(size_t queue_index, PumpPolicy pump_policy);
 
   // Sets the wakeup policy for the |queue_index| to |wakeup_policy|. By
   // default queues are created with CAN_WAKE_OTHER_QUEUES.
   void SetWakeupPolicy(size_t queue_index, WakeupPolicy wakeup_policy);
 
   // Reloads new tasks from the incoming queue for |queue_index| into the work
@@ skipping 40 matching lines @@
 
   // Returns a bitmap where a bit is set iff a task on the corresponding queue
   // was run since the last call to GetAndClearTaskWasRunOnQueueBitmap.
   uint64 GetAndClearTaskWasRunOnQueueBitmap();
 
  private:
   // TaskQueueSelector::Observer implementation:
   void OnTaskQueueEnabled() override;
 
   friend class internal::LazyNow;
-  friend class internal::TaskQueue;
+  friend class internal::TaskQueueImpl;
   friend class TaskQueueManagerTest;
 
   class DeletionSentinel : public base::RefCounted<DeletionSentinel> {
    private:
     friend class base::RefCounted<DeletionSentinel>;
     ~DeletionSentinel() {}
   };
 
   // Called by the task queue to register a new pending task.
   void DidQueueTask(const base::PendingTask& pending_task);
@@ skipping 29 matching lines @@
                                 bool has_previous_task,
                                 base::PendingTask* previous_task);
 
   bool RunsTasksOnCurrentThread() const;
   bool PostDelayedTask(const tracked_objects::Location& from_here,
                        const base::Closure& task,
                        base::TimeDelta delay);
   bool PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
                                   const base::Closure& task,
                                   base::TimeDelta delay);
-  internal::TaskQueue* Queue(size_t queue_index) const;
+  internal::TaskQueueImpl* Queue(size_t queue_index) const;
 
   base::TimeTicks Now() const;
 
   int GetNextSequenceNumber();
 
   scoped_refptr<base::trace_event::ConvertableToTraceFormat>
   AsValueWithSelectorResult(bool should_run, size_t selected_queue) const;
   static const char* PumpPolicyToString(PumpPolicy pump_policy);
   static const char* WakeupPolicyToString(WakeupPolicy wakeup_policy);
 
-  std::vector<scoped_refptr<internal::TaskQueue>> queues_;
+  std::vector<scoped_refptr<internal::TaskQueueImpl>> queues_;
   base::AtomicSequenceNumber task_sequence_num_;
   base::debug::TaskAnnotator task_annotator_;
 
   base::ThreadChecker main_thread_checker_;
   scoped_refptr<NestableSingleThreadTaskRunner> main_task_runner_;
   TaskQueueSelector* selector_;
 
   base::Closure do_work_from_main_thread_closure_;
   base::Closure do_work_from_other_thread_closure_;
 
@@ skipping 13 matching lines @@
 
   scoped_refptr<DeletionSentinel> deletion_sentinel_;
   base::WeakPtrFactory<TaskQueueManager> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(TaskQueueManager);
 };
 
 }  // namespace scheduler
 
 #endif  // CONTENT_RENDERER_SCHEDULER_TASK_QUEUE_MANAGER_H_