POC: Instrument task time tracker

components/scheduler/child/scheduler_helper.h

 // Copyright 2015 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_CHILD_SCHEDULER_HELPER_H_
 #define COMPONENTS_SCHEDULER_CHILD_SCHEDULER_HELPER_H_
 
 #include <stddef.h>
 
 #include "base/macros.h"
 #include "base/time/tick_clock.h"
 #include "components/scheduler/base/task_queue_manager.h"
 #include "components/scheduler/base/task_queue_selector.h"
+#include "components/scheduler/base/task_time_tracker.h"
 #include "components/scheduler/scheduler_export.h"
 
 namespace base {
 class TickClock;
 }
 
 namespace scheduler {
 
 class SchedulerTqmDelegate;
 
 // Common scheduler functionality for default tasks.
-class SCHEDULER_EXPORT SchedulerHelper : public TaskQueueManager::Observer {
+class SCHEDULER_EXPORT SchedulerHelper
+    : public TaskQueueManager::Observer,
+      public TaskTimeTracker::TaskTimeObserver {
  public:
   // Category strings must have application lifetime (statics or
   // literals). They may not include " chars.
   SchedulerHelper(
       scoped_refptr<SchedulerTqmDelegate> task_queue_manager_delegate,
       const char* tracing_category,
       const char* disabled_by_default_tracing_category,
       const char* disabled_by_default_verbose_tracing_category);
   ~SchedulerHelper() override;
 
   // TaskQueueManager::Observer implementation:
   void OnUnregisterTaskQueue(const scoped_refptr<TaskQueue>& queue) override;
   void OnTriedToExecuteBlockedTask(const TaskQueue& queue,
                                    const base::PendingTask& task) override;
 
+  // TaskTimeTracker::TaskTimeObserver implementation:
+  void OnLongTask(base::TimeDelta long_task_time) override;
+
   // Returns the default task runner.
   scoped_refptr<TaskQueue> DefaultTaskRunner();
 
   // Returns the control task runner.  Tasks posted to this runner are executed
   // with the highest priority. Care must be taken to avoid starvation of other
   // task queues.
   scoped_refptr<TaskQueue> ControlTaskRunner();
 
   // Returns the control task after wakeup runner.  Tasks posted to this runner
   // are executed with the highest priority but do not cause the scheduler to
@@ skipping 50 matching lines @@
 
   // Test helpers.
   void SetWorkBatchSizeForTesting(size_t work_batch_size);
   TaskQueueManager* GetTaskQueueManagerForTesting();
 
  private:
   friend class SchedulerHelperTest;
 
   base::ThreadChecker thread_checker_;
   scoped_refptr<SchedulerTqmDelegate> task_queue_manager_delegate_;
+  std::unique_ptr<TaskTimeTracker> task_time_tracker_;
   std::unique_ptr<TaskQueueManager> task_queue_manager_;
   scoped_refptr<TaskQueue> control_task_runner_;
   scoped_refptr<TaskQueue> control_after_wakeup_task_runner_;
   scoped_refptr<TaskQueue> default_task_runner_;
 
   Observer* observer_;  // NOT OWNED
   const char* tracing_category_;
   const char* disabled_by_default_tracing_category_;
 
   DISALLOW_COPY_AND_ASSIGN(SchedulerHelper);
 };
 
 }  // namespace scheduler
 
 #endif  // COMPONENTS_SCHEDULER_CHILD_SCHEDULER_HELPER_H_