chromeos: Simplify ShutdownPolicyHandler

chrome/browser/ui/ash/system_tray_delegate_chromeos.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 "chrome/browser/ui/ash/system_tray_delegate_chromeos.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <set>
@@ skipping 591 matching lines @@
 void SystemTrayDelegateChromeOS::AddShutdownPolicyObserver(
     ash::ShutdownPolicyObserver* observer) {
   shutdown_policy_observers_.AddObserver(observer);
 }
 
 void SystemTrayDelegateChromeOS::RemoveShutdownPolicyObserver(
     ash::ShutdownPolicyObserver* observer) {
   shutdown_policy_observers_.RemoveObserver(observer);
 }
 
-void SystemTrayDelegateChromeOS::ShouldRebootOnShutdown(
-    const ash::RebootOnShutdownCallback& callback) {
-  shutdown_policy_handler_->CheckIfRebootOnShutdown(callback);
+void SystemTrayDelegateChromeOS::CheckIfRebootOnShutdown() {
+  shutdown_policy_handler_->CheckIfRebootOnShutdown();
 }
 
 ash::VPNDelegate* SystemTrayDelegateChromeOS::GetVPNDelegate() const {
   return vpn_delegate_.get();
 }
 
 std::unique_ptr<ash::SystemTrayItem>
 SystemTrayDelegateChromeOS::CreateRotationLockTrayItem(ash::SystemTray* tray) {
   return base::MakeUnique<ash::TrayRotationLock>(tray);
 }
@@ skipping 442 matching lines @@
   LOG(WARNING) << "SystemTrayDelegateChromeOS::GetChildUserMessage call while "
                << "ENABLE_SUPERVISED_USERS undefined.";
   return base::string16();
 }
 
 ash::SystemTrayDelegate* CreateSystemTrayDelegate() {
   return new SystemTrayDelegateChromeOS();
 }
 
 }  // namespace chromeos