Fix a bug that could occasionaly cause setInterval to stop

components/scheduler/base/time_domain.h

 // 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.
 
 #ifndef COMPONENTS_SCHEDULER_BASE_TIME_DOMAIN_H_
 #define COMPONENTS_SCHEDULER_BASE_TIME_DOMAIN_H_
 
 #include <map>
 
 #include "base/callback.h"
@@ skipping 32 matching lines @@
   virtual ~TimeDomain();
 
   // Returns a LazyNow that evaluate this TimeDomain's Now.  Can be called from
   // any thread.
   // TODO(alexclarke): Make this main thread only.
   virtual LazyNow CreateLazyNow() const = 0;
 
   // Evaluate this TimeDomain's Now. Can be called from any thread.
   virtual base::TimeTicks Now() const = 0;
 
-  // Computes a runtime which is >= |time_domain_now| + |delay|. This is used to
-  // allow the TimeDomain to decide if the real or virtual time should be used
-  // when computing the task run time.  This can be called from any thread.
-  virtual base::TimeTicks ComputeDelayedRunTime(
-      base::TimeTicks time_domain_now,
-      base::TimeDelta delay) const = 0;
-
   // Some TimeDomains support virtual time, this method tells us to advance time
   // if possible and return true if time was advanced.
   virtual bool MaybeAdvanceTime() = 0;
 
   // Returns the name of this time domain for tracing.
   virtual const char* GetName() const = 0;
 
   // If there is a scheduled delayed task, |out_time| is set to the scheduled
   // runtime for the next one and it returns true.  Returns false otherwise.
   bool NextScheduledRunTime(base::TimeTicks* out_time) const;
 
+  // Clears expired entries from |delayed_wakeup_multimap_|. Caution needs to be
+  // taken to ensure TaskQueueImpl::UpdateDelayedWorkQueue or
+  // TaskQueueImpl::Pump is called on the affected queues.
+  void ClearExpiredWakeups();

[rmcilroy, 2016/07/18 15:22:57]

Did this need to be moved? I don't see it being used anywhere it wasn't
previously.

[alex clarke (OOO till 29th), 2016/07/18 15:35:52]

I made it public.

[rmcilroy, 2016/07/18 16:01:42]

Right, my point was why did you need to make it Public?

[alex clarke (OOO till 29th), 2016/07/18 16:06:38]

It's used by ThrottlingHelper::PumpThrottledTasks.  Note the VirtualTimeDomain
made it public with "using TimeDomain::ClearExpiredWakeups;"

I suppose we could do something similar for ThrottledTimeDomain instead. 

[rmcilroy, 2016/07/18 16:10:44]

Ahh I see. I think it's better now that it's explicitly public rather than being
exposed in a subclass.

+
  protected:
   friend class internal::TaskQueueImpl;
   friend class TaskQueueManager;
 
   void AsValueInto(base::trace_event::TracedValue* state) const;
 
   // Migrates |queue| from this time domain to |destination_time_domain|.
   void MigrateQueue(internal::TaskQueueImpl* queue,
                     TimeDomain* destination_time_domain);
 
@@ skipping 41 matching lines @@
   virtual void AsValueIntoInternal(
       base::trace_event::TracedValue* state) const = 0;
 
   // Call TaskQueueImpl::UpdateDelayedWorkQueue for each queue where the delay
   // has elapsed.
   void WakeupReadyDelayedQueues(
       LazyNow* lazy_now,
       bool should_trigger_wakeup,
       const internal::TaskQueueImpl::Task* previous_task);
 
- protected:
-  // Clears expired entries from |delayed_wakeup_multimap_|. Caution needs to be
-  // taken to ensure TaskQueueImpl::UpdateDelayedWorkQueue or
-  // TaskQueueImpl::Pump is called on the affected queues.
-  void ClearExpiredWakeups();
-
  private:
   void MoveNewlyUpdatableQueuesIntoUpdatableQueueSet();
 
   typedef std::multimap<base::TimeTicks, internal::TaskQueueImpl*>
       DelayedWakeupMultimap;
 
   DelayedWakeupMultimap delayed_wakeup_multimap_;
 
   // This lock guards only |newly_updatable_|.  It's not expected to be heavily
   // contended.
   base::Lock newly_updatable_lock_;
   std::vector<internal::TaskQueueImpl*> newly_updatable_;
 
   // Set of task queues with avaliable work on the incoming queue.  This should
   // only be accessed from the main thread.
   std::set<internal::TaskQueueImpl*> updatable_queue_set_;
 
   Observer* observer_;  // NOT OWNED.
 
   base::ThreadChecker main_thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(TimeDomain);
 };
 
 }  // namespace scheduler
 
 #endif  // COMPONENTS_SCHEDULER_BASE_TIME_DOMAIN_H_