Implement PostDelayedTaskAt for guaranteed timer ordering

components/scheduler/child/scheduler_helper.cc

 // 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.
 
 #include "components/scheduler/child/scheduler_helper.h"
 
 #include "base/time/default_tick_clock.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "components/scheduler/child/nestable_single_thread_task_runner.h"
+#include "components/scheduler/child/task_queue.h"
 
 namespace scheduler {
 
 SchedulerHelper::SchedulerHelper(
     scoped_refptr<NestableSingleThreadTaskRunner> main_task_runner,
     const char* tracing_category,
     const char* disabled_by_default_tracing_category,
     const char* disabled_by_default_verbose_tracing_category,
     size_t total_task_queue_count)
     : task_queue_selector_(new PrioritizingTaskQueueSelector()),
@@ skipping 46 matching lines @@
 }
 
 SchedulerHelper::~SchedulerHelper() {
 }
 
 void SchedulerHelper::Shutdown() {
   CheckOnValidThread();
   task_queue_manager_.reset();
 }
 
-scoped_refptr<base::SingleThreadTaskRunner>
-SchedulerHelper::DefaultTaskRunner() {
+scoped_refptr<TaskQueue> SchedulerHelper::DefaultTaskRunner() {
   CheckOnValidThread();
   return default_task_runner_;
 }
 
 scoped_refptr<base::SingleThreadTaskRunner>
 SchedulerHelper::ControlTaskRunner() {
   return control_task_runner_;
 }
 
 scoped_refptr<base::SingleThreadTaskRunner>
@@ skipping 14 matching lines @@
 
 TaskQueueManager* SchedulerHelper::GetTaskQueueManagerForTesting() {
   CheckOnValidThread();
   return task_queue_manager_.get();
 }
 
 base::TimeTicks SchedulerHelper::Now() const {
   return time_source_->NowTicks();
 }
 
-scoped_refptr<base::SingleThreadTaskRunner> SchedulerHelper::TaskRunnerForQueue(
+scoped_refptr<TaskQueue> SchedulerHelper::TaskRunnerForQueue(
     size_t queue_index) const {
   CheckOnValidThread();
   return task_queue_manager_->TaskRunnerForQueue(queue_index);
 }
 
 base::TimeTicks SchedulerHelper::NextPendingDelayedTaskRunTime() const {
   CheckOnValidThread();
   return task_queue_manager_->NextPendingDelayedTaskRunTime();
 }
 
@@ skipping 88 matching lines @@
 }
 
 void SchedulerHelper::RemoveTaskObserver(
     base::MessageLoop::TaskObserver* task_observer) {
   CheckOnValidThread();
   if (task_queue_manager_)
     task_queue_manager_->RemoveTaskObserver(task_observer);
 }
 
 }  // namespace scheduler