Convert //ash from scoped_ptr to std::unique_ptr

ash/metrics/user_metrics_recorder.h

 // Copyright 2013 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 ASH_METRICS_USER_METRICS_RECORDER_H_
 #define ASH_METRICS_USER_METRICS_RECORDER_H_
 
+#include <memory>
+
 #include "ash/ash_export.h"
 #include "ash/metrics/task_switch_metrics_recorder.h"
 #include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
 #include "base/timer/timer.h"
 
 namespace ash {
 
 class DesktopTaskSwitchMetricRecorder;
 
 namespace test {
 class UserMetricsRecorderTestAPI;
 }
 
@@ skipping 164 matching lines @@
   // Starts the |timer_| and binds it to |RecordPeriodicMetrics|.
   void StartTimer();
 
   // The periodic timer that triggers metrics to be recorded.
   base::RepeatingTimer timer_;
 
   TaskSwitchMetricsRecorder task_switch_metrics_recorder_;
 
   // Metric recorder to track how often task windows are activated by mouse
   // clicks or touchscreen taps.
-  scoped_ptr<DesktopTaskSwitchMetricRecorder>
+  std::unique_ptr<DesktopTaskSwitchMetricRecorder>
       desktop_task_switch_metric_recorder_;
 
   DISALLOW_COPY_AND_ASSIGN(UserMetricsRecorder);
 };
 
 }  // namespace ash
 
 #endif  // ASH_METRICS_USER_METRICS_RECORDER_H_