Convert //ash from scoped_ptr to std::unique_ptr

ash/system/chromeos/screen_security/screen_capture_tray_item.cc

 // 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.
 
 #include "ash/system/chromeos/screen_security/screen_capture_tray_item.h"
 
 #include <utility>
 
 #include "ash/shell.h"
 #include "ash/system/system_notifier.h"
@@ skipping 41 matching lines @@
       l10n_util::GetStringUTF16(
           IDS_ASH_STATUS_TRAY_SCREEN_CAPTURE_STOP)));
   return default_view();
 }
 
 void ScreenCaptureTrayItem::CreateOrUpdateNotification() {
   message_center::RichNotificationData data;
   data.buttons.push_back(message_center::ButtonInfo(
       l10n_util::GetStringUTF16(IDS_ASH_STATUS_TRAY_SCREEN_CAPTURE_STOP)));
   ui::ResourceBundle& resource_bundle = ui::ResourceBundle::GetSharedInstance();
-  scoped_ptr<Notification> notification(new Notification(
+  std::unique_ptr<Notification> notification(new Notification(
       message_center::NOTIFICATION_TYPE_SIMPLE, kScreenCaptureNotificationId,
       screen_capture_status_, base::string16() /* body is blank */,
       resource_bundle.GetImageNamed(IDR_AURA_UBER_TRAY_SCREENSHARE_DARK),
       base::string16() /* display_source */, GURL(),
       message_center::NotifierId(message_center::NotifierId::SYSTEM_COMPONENT,
                                  system_notifier::kNotifierScreenCapture),
       data, new tray::ScreenNotificationDelegate(this)));
   notification->SetSystemPriority();
   message_center::MessageCenter::Get()->AddNotification(
       std::move(notification));
@@ skipping 26 matching lines @@
   // screen capture is stopped externally.
   set_is_started(false);
   Update();
 }
 
 void ScreenCaptureTrayItem::OnCastingSessionStartedOrStopped(bool started) {
   is_casting_ = started;
 }
 
 }  // namespace ash