Add testRunner.runIdleTasks() to force idle tasks to run.

components/scheduler/renderer/renderer_scheduler_impl.h

 // Copyright 2014 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_RENDERER_RENDERER_SCHEDULER_IMPL_H_
 #define COMPONENTS_SCHEDULER_RENDERER_RENDERER_SCHEDULER_IMPL_H_
 
 #include "base/atomicops.h"
 #include "base/macros.h"
 #include "base/synchronization/lock.h"
@@ skipping 88 matching lines @@
 
   void AddWebViewScheduler(WebViewSchedulerImpl* web_view_scheduler);
   void RemoveWebViewScheduler(WebViewSchedulerImpl* web_view_scheduler);
 
   // Test helpers.
   SchedulerHelper* GetSchedulerHelperForTesting();
   TaskCostEstimator* GetLoadingTaskCostEstimatorForTesting();
   TaskCostEstimator* GetTimerTaskCostEstimatorForTesting();
   IdleTimeEstimator* GetIdleTimeEstimatorForTesting();
   base::TimeTicks CurrentIdleTaskDeadlineForTesting() const;
+  void RunIdleTasksForTesting(const base::Closure&);

[Sami, 2016/04/06 15:52:37]

nit: Please name the parameter (Chromium style doesn't strictly require it but
the code here has names for everything).

[szager1, 2016/04/06 17:55:30]

Done.

 
   base::TickClock* tick_clock() const;
 
   RealTimeDomain* real_time_domain() const {
     return helper_.real_time_domain();
   }
 
   ThrottlingHelper* throttling_helper() { return throttling_helper_.get(); }
 
  private:
@@ skipping 58 matching lines @@
 
   // IdleHelper::Delegate implementation:
   bool CanEnterLongIdlePeriod(
       base::TimeTicks now,
       base::TimeDelta* next_long_idle_period_delay_out) override;
   void IsNotQuiescent() override {}
   void OnIdlePeriodStarted() override;
   void OnIdlePeriodEnded() override;
 
   void EndIdlePeriod();
+  void EndIdlePeriodForTesting(
+      const base::Closure& callback,
+      base::TimeTicks time_remaining);

[Sami, 2016/04/06 15:52:37]

Did you mean to remove this parameter?

Also, the callback doesn't seem that useful since it is just synchronously
executed.

[szager1, 2016/04/06 17:55:30]

Because this is posted as an idle task, it has to match the IdleTask interface,
which takes a TimeTicks argument.

The callback is useful because it runs *after* the call to EndIdlePeriod().  In
some cases, I'd like to be able to write test code that does not run during idle
time:

requestIdleCallback(testFunction1);
testRunner.runIdleTasks(() => {
  // Guaranteed not to be in idle time.
  requestIdleCallback(testFunction2);
  requestAnimationFrame(() => {
    // Guaranteed that testFunction2 has not yet run.
  });
});

[Sami, 2016/04/06 18:01:58]

Ah sorry, I wasn't paying attention while reading this. Somehow I thought this
was part of the public interface.

 
   // Returns the serialized scheduler state for tracing.
   scoped_ptr<base::trace_event::ConvertableToTraceFormat> AsValue(
       base::TimeTicks optional_now) const;
   scoped_ptr<base::trace_event::ConvertableToTraceFormat> AsValueLocked(
       base::TimeTicks optional_now) const;
 
   static bool ShouldPrioritizeInputEvent(
       const blink::WebInputEvent& web_input_event);
 
@@ skipping 139 matching lines @@
     bool was_shutdown;
     bool loading_tasks_seem_expensive;
     bool timer_tasks_seem_expensive;
     bool touchstart_expected_soon;
     bool have_seen_a_begin_main_frame;
     bool have_reported_blocking_intervention_in_current_policy;
     bool have_reported_blocking_intervention_since_navigation;
     bool has_visible_render_widget_with_touch_handler;
     bool begin_frame_not_expected_soon;
     bool expensive_task_blocking_allowed;
+    bool in_idle_period_for_testing;
     std::set<WebViewSchedulerImpl*> web_view_schedulers_;  // Not owned.
   };
 
   struct AnyThread {
     AnyThread();
     ~AnyThread();
 
     base::TimeTicks last_idle_period_end_time;
     base::TimeTicks rails_loading_priority_deadline;
     base::TimeTicks fling_compositor_escalation_deadline;
@@ skipping 55 matching lines @@
 
   PollableThreadSafeFlag policy_may_need_update_;
   base::WeakPtrFactory<RendererSchedulerImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RendererSchedulerImpl);
 };
 
 }  // namespace scheduler
 
 #endif  // COMPONENTS_SCHEDULER_RENDERER_RENDERER_SCHEDULER_IMPL_H_