Convert //base to use std::unique_ptr

base/memory/memory_pressure_monitor_mac.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 BASE_MEMORY_MEMORY_PRESSURE_MONITOR_MAC_H_
 #define BASE_MEMORY_MEMORY_PRESSURE_MONITOR_MAC_H_
 
 #include <dispatch/dispatch.h>
 
 #include "base/base_export.h"
@@ skipping 34 matching lines @@
   // Returns the currently-observed memory pressure.
   MemoryPressureLevel GetCurrentPressureLevel() const override;
 
  private:
   friend TestMemoryPressureMonitor;
 
   static MemoryPressureLevel
       MemoryPressureLevelForMacMemoryPressure(int mac_memory_pressure);
   static void NotifyMemoryPressureChanged(dispatch_source_s* event_source);
 
-  scoped_ptr<dispatch_source_s, DispatchSourceSDeleter>
+  std::unique_ptr<dispatch_source_s, DispatchSourceSDeleter>
       memory_level_event_source_;
 
   DISALLOW_COPY_AND_ASSIGN(MemoryPressureMonitor);
 };
 
 }  // namespace mac
 }  // namespace base
 
 #endif  // BASE_MEMORY_MEMORY_PRESSURE_MONITOR_MAC_H_