(reland) Adds TimeDomains to the TaskQueueManager

components/scheduler/base/task_queue_manager.cc

Index: components/scheduler/base/task_queue_manager.cc
diff --git a/components/scheduler/base/task_queue_manager.cc b/components/scheduler/base/task_queue_manager.cc
index 2f557355deda5b264f93b01d47535009bd0ed9a2..b0ad376da4c76e0f7c5317193c00dffbc1a877ac 100644
--- a/components/scheduler/base/task_queue_manager.cc
+++ b/components/scheduler/base/task_queue_manager.cc
@@ -8,7 +8,7 @@
 #include <set>
 
 #include "base/bind.h"
-#include "components/scheduler/base/lazy_now.h"
+#include "components/scheduler/base/delayed_task_delegate_impl.h"
 #include "components/scheduler/base/task_queue_impl.h"
 #include "components/scheduler/base/task_queue_manager_delegate.h"
 #include "components/scheduler/base/task_queue_selector.h"
@@ -46,6 +46,9 @@ TaskQueueManager::TaskQueueManager(
       base::Bind(&TaskQueueManager::DoWork, weak_factory_.GetWeakPtr(), true);
   do_work_closure_ =
       base::Bind(&TaskQueueManager::DoWork, weak_factory_.GetWeakPtr(), false);
+
+  delayed_task_delegate_ = make_scoped_refptr(
+      new DelayedTaskDelegateImpl(delegate.get(), do_work_closure_));
 }
 
 TaskQueueManager::~TaskQueueManager() {
@@ -65,7 +68,9 @@ scoped_refptr<internal::TaskQueueImpl> TaskQueueManager::NewTaskQueue(
   DCHECK(main_thread_checker_.CalledOnValidThread());
   scoped_refptr<internal::TaskQueueImpl> queue(
       make_scoped_refptr(new internal::TaskQueueImpl(
-          this, spec, disabled_by_default_tracing_category_,
+          this, spec.delayed_task_delegate ? spec.delayed_task_delegate
+                                           : delayed_task_delegate_,
+          spec, disabled_by_default_tracing_category_,
           disabled_by_default_verbose_tracing_category_)));
   queues_.insert(queue);
   selector_.AddQueue(queue.get());
@@ -92,20 +97,6 @@ void TaskQueueManager::UnregisterTaskQueue(
   queues_.erase(task_queue);
   selector_.RemoveQueue(task_queue.get());
 
-  // We need to remove |task_queue| from delayed_wakeup_multimap_ which is a
-  // little awkward since it's keyed by time. O(n) running time.
-  for (DelayedWakeupMultimap::iterator iter = delayed_wakeup_multimap_.begin();
-       iter != delayed_wakeup_multimap_.end();) {
-    if (iter->second == task_queue.get()) {
-      DelayedWakeupMultimap::iterator temp = iter;
-      iter++;
-      // O(1) amortized.
-      delayed_wakeup_multimap_.erase(temp);
-    } else {
-      iter++;
-    }
-  }
-
   // |newly_updatable_| might contain |task_queue|, we use
   // MoveNewlyUpdatableQueuesIntoUpdatableQueueSet to flush it out.
   MoveNewlyUpdatableQueuesIntoUpdatableQueueSet();
@@ -171,10 +162,10 @@ void TaskQueueManager::UpdateWorkQueues(
   DCHECK(main_thread_checker_.CalledOnValidThread());
   TRACE_EVENT0(disabled_by_default_tracing_category_,
                "TaskQueueManager::UpdateWorkQueues");
-  internal::LazyNow lazy_now(delegate().get());
+  delayed_task_delegate_->InvalidateNowCache();
 
   // Move any ready delayed tasks into the incomming queues.
-  WakeupReadyDelayedQueues(&lazy_now);
+  delayed_task_delegate_->WakeupReadyDelayedQueues();
 
   MoveNewlyUpdatableQueuesIntoUpdatableQueueSet();
 
@@ -185,62 +176,7 @@ void TaskQueueManager::UpdateWorkQueues(
     // This is fine, erasing an element won't invalidate any interator, as long
     // as the iterator isn't the element being delated.
     if (queue->work_queue().empty())
-      queue->UpdateWorkQueue(&lazy_now, should_trigger_wakeup, previous_task);
-  }
-}
-
-void TaskQueueManager::ScheduleDelayedWorkTask(
-    scoped_refptr<internal::TaskQueueImpl> queue,
-    base::TimeTicks delayed_run_time) {
-  internal::LazyNow lazy_now(delegate().get());
-  ScheduleDelayedWork(queue.get(), delayed_run_time, &lazy_now);
-}
-
-void TaskQueueManager::ScheduleDelayedWork(internal::TaskQueueImpl* queue,
-                                           base::TimeTicks delayed_run_time,
-                                           internal::LazyNow* lazy_now) {
-  if (!delegate_->BelongsToCurrentThread()) {
-    // NOTE posting a delayed task from a different thread is not expected to be
-    // common. This pathway is less optimal than perhaps it could be because
-    // it causes two main thread tasks to be run.  Should this assumption prove
-    // to be false in future, we may need to revisit this.
-    delegate_->PostTask(
-        FROM_HERE, base::Bind(&TaskQueueManager::ScheduleDelayedWorkTask,
-                              weak_factory_.GetWeakPtr(),
-                              scoped_refptr<internal::TaskQueueImpl>(queue),
-                              delayed_run_time));
-    return;
-  }
-
-  // Make sure there's one (and only one) task posted to |delegate_|
-  // to call |DelayedDoWork| at |delayed_run_time|.
-  if (delayed_wakeup_multimap_.find(delayed_run_time) ==
-      delayed_wakeup_multimap_.end()) {
-    base::TimeDelta delay =
-        std::max(base::TimeDelta(), delayed_run_time - lazy_now->Now());
-    delegate_->PostDelayedTask(FROM_HERE, do_work_closure_, delay);
-  }
-  delayed_wakeup_multimap_.insert(std::make_pair(delayed_run_time, queue));
-}
-
-void TaskQueueManager::WakeupReadyDelayedQueues(internal::LazyNow* lazy_now) {
-  // Wake up any queues with pending delayed work.  Note std::multipmap stores
-  // the elements sorted by key, so the begin() iterator points to the earliest
-  // queue to wakeup.
-  std::set<internal::TaskQueueImpl*> dedup_set;
-  while (!delayed_wakeup_multimap_.empty()) {
-    DelayedWakeupMultimap::iterator next_wakeup =
-        delayed_wakeup_multimap_.begin();
-    if (next_wakeup->first > lazy_now->Now())
-      break;
-    // A queue could have any number of delayed tasks pending so it's worthwhile
-    // deduping calls to MoveReadyDelayedTasksToIncomingQueue since it takes a
-    // lock.  NOTE the order in which these are called matters since the order
-    // in which EnqueueTaskLocks is called is respected when choosing which
-    // queue to execute a task from.
-    if (dedup_set.insert(next_wakeup->second).second)
-      next_wakeup->second->MoveReadyDelayedTasksToIncomingQueue(lazy_now);
-    delayed_wakeup_multimap_.erase(next_wakeup);
+      queue->UpdateWorkQueue(should_trigger_wakeup, previous_task);
   }
 }