Convert //ash from scoped_ptr to std::unique_ptr

ash/system/tray/system_tray_delegate.cc

 // Copyright (c) 2012 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 "ash/system/tray/system_tray_delegate.h"
 
 namespace ash {
 
 NetworkIconInfo::NetworkIconInfo()
     : connecting(false),
@@ skipping 220 matching lines @@
 NetworkingConfigDelegate* SystemTrayDelegate::GetNetworkingConfigDelegate()
     const {
   return nullptr;
 }
 
 VolumeControlDelegate* SystemTrayDelegate::GetVolumeControlDelegate() const {
   return nullptr;
 }
 
 void SystemTrayDelegate::SetVolumeControlDelegate(
-    scoped_ptr<VolumeControlDelegate> delegate) {
-}
+    std::unique_ptr<VolumeControlDelegate> delegate) {}
 
 bool SystemTrayDelegate::GetSessionStartTime(
     base::TimeTicks* session_start_time) {
   return false;
 }
 
 bool SystemTrayDelegate::GetSessionLengthLimit(
     base::TimeDelta* session_length_limit) {
   return false;
 }
@@ skipping 27 matching lines @@
 
 void SystemTrayDelegate::ShouldRebootOnShutdown(
     const RebootOnShutdownCallback& callback) {
 }
 
 VPNDelegate* SystemTrayDelegate::GetVPNDelegate() const {
   return nullptr;
 }
 
 }  // namespace ash