Revert of Adds TimeDomains to the TaskQueueManager

components/scheduler/child/idle_helper.cc

Index: components/scheduler/child/idle_helper.cc
diff --git a/components/scheduler/child/idle_helper.cc b/components/scheduler/child/idle_helper.cc
index f007baec665c1234173c7ebc2a37f773a9709017..84f61712e0baf52782ee53f443facbef2200fa4d 100644
--- a/components/scheduler/child/idle_helper.cc
+++ b/components/scheduler/child/idle_helper.cc
@@ -7,7 +7,6 @@
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
-#include "components/scheduler/base/real_time_domain.h"
 #include "components/scheduler/base/task_queue.h"
 #include "components/scheduler/base/task_queue_manager.h"
 #include "components/scheduler/child/scheduler_helper.h"
@@ -77,17 +76,17 @@
     return IdlePeriodState::NOT_IN_IDLE_PERIOD;
   }
 
-  base::TimeTicks next_pending_delayed_task;
+  base::TimeTicks next_pending_delayed_task =
+      helper_->NextPendingDelayedTaskRunTime();
   base::TimeDelta max_long_idle_period_duration =
       base::TimeDelta::FromMilliseconds(kMaximumIdlePeriodMillis);
   base::TimeDelta long_idle_period_duration;
-  if (helper_->real_time_domain()->NextScheduledRunTime(
-          &next_pending_delayed_task)) {
+  if (next_pending_delayed_task.is_null()) {
+    long_idle_period_duration = max_long_idle_period_duration;
+  } else {
     // Limit the idle period duration to be before the next pending task.
     long_idle_period_duration = std::min(next_pending_delayed_task - now,
                                          max_long_idle_period_duration);
-  } else {
-    long_idle_period_duration = max_long_idle_period_duration;
   }
 
   if (long_idle_period_duration >=