Optimize away updatable_queue_set_

third_party/WebKit/Source/platform/scheduler/base/time_domain.h

Index: third_party/WebKit/Source/platform/scheduler/base/time_domain.h
diff --git a/third_party/WebKit/Source/platform/scheduler/base/time_domain.h b/third_party/WebKit/Source/platform/scheduler/base/time_domain.h
index 639d1742a35feec99c4355430a72a7ab048b076a..3ab2e68f42f9caa6d65ceaa5b3c70bd82412d87e 100644
--- a/third_party/WebKit/Source/platform/scheduler/base/time_domain.h
+++ b/third_party/WebKit/Source/platform/scheduler/base/time_domain.h
@@ -90,7 +90,7 @@ class BLINK_PLATFORM_EXPORT TimeDomain {
 
   // Adds |queue| to the set of task queues that UpdateWorkQueues calls

[Sami, 2017/01/18 17:57:04]

This comment looks out of date now.

Also, could you mention that this can be called on any thread?

[alex clarke (OOO till 29th), 2017/01/19 08:50:52]

Done.

   // UpdateWorkQueue on.
-  void RegisterAsUpdatableTaskQueue(internal::TaskQueueImpl* queue);
+  void OnQueueHasIncomingImmediateWork(internal::TaskQueueImpl* queue);
 
   // Schedules a call to TaskQueueImpl::WakeUpForDelayedWork when this
   // TimeDomain reaches |delayed_run_time|.  This supersedes any previously
@@ -102,10 +102,6 @@ class BLINK_PLATFORM_EXPORT TimeDomain {
   // Registers the |queue|.
   void RegisterQueue(internal::TaskQueueImpl* queue);
 
-  // Removes |queue| from the set of task queues that UpdateWorkQueues calls
-  // UpdateWorkQueue on. Returns true if |queue| was updatable.
-  bool UnregisterAsUpdatableTaskQueue(internal::TaskQueueImpl* queue);
-
   // Removes |queue| from all internal data structures.
   void UnregisterQueue(internal::TaskQueueImpl* queue);
 
@@ -136,8 +132,6 @@ class BLINK_PLATFORM_EXPORT TimeDomain {
   }
 
  private:
-  void MoveNewlyUpdatableQueuesIntoUpdatableQueueSet();
-
   struct DelayedWakeup {
     base::TimeTicks time;
     internal::TaskQueueImpl* queue;
@@ -164,14 +158,13 @@ class BLINK_PLATFORM_EXPORT TimeDomain {
 
   IntrusiveHeap<DelayedWakeup> delayed_wakeup_queue_;
 
-  // 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_;
+  // This lock guards only |has_incoming_immediate_work_|.  It's not expected to
+  // be heavily contended.
+  mutable base::Lock has_incoming_immediate_work_lock_;
 
   // Set of task queues with avaliable work on the incoming queue.  This should

[Sami, 2017/01/18 17:57:04]

Is the second sentence still valid? If it's main-thread only, then it doesn't
need a lock :)

[alex clarke (OOO till 29th), 2017/01/19 08:50:52]

Done.

   // only be accessed from the main thread.
-  std::set<internal::TaskQueueImpl*> updatable_queue_set_;
+  std::set<internal::TaskQueueImpl*> has_incoming_immediate_work_;
 
   Observer* observer_;  // NOT OWNED.