POC: Instrument task time tracker

components/scheduler/base/task_time_tracker.cc

Index: components/scheduler/base/task_time_tracker.cc
diff --git a/components/scheduler/base/task_time_tracker.cc b/components/scheduler/base/task_time_tracker.cc
new file mode 100644
index 0000000000000000000000000000000000000000..bbdc050e84f674f150d21ca09d26b353844feaad
--- /dev/null
+++ b/components/scheduler/base/task_time_tracker.cc
@@ -0,0 +1,30 @@
+// Copyright 2016 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.
+
+#include "components/scheduler/base/task_time_tracker.h"
+
+namespace scheduler {
+
+TaskTimeTracker::TaskTimeTracker()
+    : task_time_observer_(nullptr) {}
+
+TaskTimeTracker::~TaskTimeTracker() {}
+
+void TaskTimeTracker::SetObserver(TaskTimeObserver* task_time_observer) {
+  task_time_observer_ = task_time_observer;
+}
+
+void TaskTimeTracker::ReportTaskTime(
+    base::TimeTicks task_start_time, base::TimeTicks task_end_time) {
+  base::TimeDelta task_duration = task_end_time - task_start_time;
+  if (task_duration.InMicroseconds() > 50000) {  // make constant
+    /*
+    if (task_time_observer_ != nullptr) {
+      task_time_observer_->OnLongTask(task_duration);
+    }
+    */
+  }
+}
+
+} // scheduler