Move and rename TaskTimeTracker to public interface exposed to WebThread, use in WebPerf Agent.

third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h

Index: third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h
diff --git a/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h b/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h
index 77705b4627e7dc60e28fb7bebe752781e99bd79e..a0944dfad3ec8fd37376b25d5a874fa33335aa4c 100644
--- a/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h
+++ b/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.h
@@ -8,7 +8,6 @@
 #include "base/atomicops.h"
 #include "base/macros.h"
 #include "base/synchronization/lock.h"
-#include "platform/scheduler/base/long_task_tracker.h"
 #include "platform/scheduler/base/pollable_thread_safe_flag.h"
 #include "platform/scheduler/base/queueing_time_estimator.h"
 #include "platform/scheduler/base/task_time_tracker.h"
@@ -149,7 +148,8 @@ class BLINK_PLATFORM_EXPORT RendererSchedulerImpl
   void AddWebViewScheduler(WebViewSchedulerImpl* web_view_scheduler);
   void RemoveWebViewScheduler(WebViewSchedulerImpl* web_view_scheduler);
 
-  LongTaskTracker::LongTaskTiming GetLongTaskTiming();
+  void AddTaskTimeObserver(WebThread::TaskTimeObserver* task_time_observer);
+  void RemoveTaskTimeObserver(WebThread::TaskTimeObserver* task_time_observer);
 
   // Test helpers.
   SchedulerHelper* GetSchedulerHelperForTesting();
@@ -380,7 +380,6 @@ class BLINK_PLATFORM_EXPORT RendererSchedulerImpl
     TaskCostEstimator loading_task_cost_estimator;
     TaskCostEstimator timer_task_cost_estimator;
     QueueingTimeEstimator queueing_time_estimator;
-    LongTaskTracker long_task_tracker;
     IdleTimeEstimator idle_time_estimator;
     UseCase current_use_case;
     Policy current_policy;