Report the duration of sampled tasks with histogram.

components/scheduler/renderer/renderer_scheduler_impl.h

Index: components/scheduler/renderer/renderer_scheduler_impl.h
diff --git a/components/scheduler/renderer/renderer_scheduler_impl.h b/components/scheduler/renderer/renderer_scheduler_impl.h
index d662dd45247bfbc44717b04897dc22e3ae2eed74..5fcb5b9efa7d37bf7989aaa9dd1ffc5edb4639ec 100644
--- a/components/scheduler/renderer/renderer_scheduler_impl.h
+++ b/components/scheduler/renderer/renderer_scheduler_impl.h
@@ -19,6 +19,7 @@
 #include "components/scheduler/renderer/render_widget_signals.h"
 #include "components/scheduler/renderer/renderer_scheduler.h"
 #include "components/scheduler/renderer/task_cost_estimator.h"
+#include "components/scheduler/renderer/task_duration_reporter.h"
 #include "components/scheduler/renderer/throttling_helper.h"
 #include "components/scheduler/renderer/user_model.h"
 #include "components/scheduler/renderer/web_view_scheduler_impl.h"
@@ -378,6 +379,7 @@ class SCHEDULER_EXPORT RendererSchedulerImpl
     IdleTimeEstimator idle_time_estimator;
     UseCase current_use_case;
     Policy current_policy;
+    TaskDurationReporter duration_reporter;
     base::TimeTicks current_policy_expiration_time;
     base::TimeTicks estimated_next_frame_begin;
     base::TimeDelta compositor_frame_interval;
@@ -470,6 +472,7 @@ class SCHEDULER_EXPORT RendererSchedulerImpl
   }
 
   PollableThreadSafeFlag policy_may_need_update_;
+

[majidvp, 2016/07/27 20:05:42]

nit: frivolous blank line

   base::WeakPtrFactory<RendererSchedulerImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RendererSchedulerImpl);