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

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

Index: third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.cc
diff --git a/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.cc b/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.cc
index 9da5037f8a53dcde487cf8d06e8b5b77806b4c04..1c1a8fcf2d924320795aa261556a5efb614a6175 100644
--- a/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.cc
+++ b/third_party/WebKit/Source/platform/scheduler/renderer/renderer_scheduler_impl.cc
@@ -36,6 +36,13 @@ const double kShortIdlePeriodDurationPercentile = 50;
 // Amount of idle time left in a frame (as a ratio of the vsync interval) above
 // which main thread compositing can be considered fast.
 const double kFastCompositingIdleTimeThreshold = .2;
+
+base::TimeTicks MonotonicTimeInSecondsToTimeTicks(
+    double monotonicTimeInSeconds) {
+  return base::TimeTicks::FromInternalValue(monotonicTimeInSeconds *
+                                            base::Time::kMicrosecondsPerSecond);
+}
+
 }  // namespace
 
 RendererSchedulerImpl::RendererSchedulerImpl(
@@ -81,7 +88,7 @@ RendererSchedulerImpl::RendererSchedulerImpl(
       this);
 
   helper_.SetObserver(this);
-  helper_.SetTaskTimeTracker(this);
+  helper_.AddTaskTimeTracker(this);
 }
 
 RendererSchedulerImpl::~RendererSchedulerImpl() {
@@ -101,6 +108,8 @@ RendererSchedulerImpl::~RendererSchedulerImpl() {
   if (virtual_time_domain_)
     UnregisterTimeDomain(virtual_time_domain_.get());
 
+  helper_.RemoveTaskTimeTracker(this);
+
   // Ensure the renderer scheduler was shut down explicitly, because otherwise
   // we could end up having stale pointers to the Blink heap which has been
   // terminated by this point.
@@ -1415,19 +1424,26 @@ void RendererSchedulerImpl::OnTriedToExecuteBlockedTask(
   }
 }
 
-void RendererSchedulerImpl::ReportTaskTime(base::TimeTicks start_time,
-                                           base::TimeTicks end_time) {
-  MainThreadOnly().queueing_time_estimator.OnToplevelTaskCompleted(start_time,
-                                                                   end_time);
-  MainThreadOnly().long_task_tracker.RecordLongTask(
-      start_time, end_time - start_time);
-  UMA_HISTOGRAM_CUSTOM_COUNTS("RendererScheduler.TaskTime",
-                              (end_time - start_time).InMicroseconds(), 1,
-                              1000000, 50);
+void RendererSchedulerImpl::ReportTaskTime(double start_time, double end_time) {
+  base::TimeTicks start_time_ticks =
+      MonotonicTimeInSecondsToTimeTicks(start_time);
+  base::TimeTicks end_time_ticks = MonotonicTimeInSecondsToTimeTicks(end_time);
+
+  MainThreadOnly().queueing_time_estimator.OnToplevelTaskCompleted(
+      start_time_ticks, end_time_ticks);
+  UMA_HISTOGRAM_CUSTOM_COUNTS(
+      "RendererScheduler.TaskTime",
+      (end_time_ticks - start_time_ticks).InMicroseconds(), 1, 1000000, 50);
+}
+
+void RendererSchedulerImpl::AddTaskTimeTracker(
+    TaskTimeTracker* task_time_tracker) {
+  helper_.AddTaskTimeTracker(task_time_tracker);
 }
 
-LongTaskTracker::LongTaskTiming RendererSchedulerImpl::GetLongTaskTiming() {
-  return MainThreadOnly().long_task_tracker.GetLongTaskTiming();
+void RendererSchedulerImpl::RemoveTaskTimeTracker(
+    TaskTimeTracker* task_time_tracker) {
+  helper_.RemoveTaskTimeTracker(task_time_tracker);
 }
 
 void RendererSchedulerImpl::OnQueueingTimeForWindowEstimated(