Fix regression in handling toggle mirror mode

ash/accelerators/accelerator_controller_delegate_aura.cc

 // Copyright 2016 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/accelerators/accelerator_controller_delegate_aura.h"
 
 #include <algorithm>
 #include <cmath>
 #include <string>
 #include <utility>
@@ skipping 339 matching lines @@
     case ROTATE_WINDOW:
     case SHOW_SYSTEM_TRAY_BUBBLE:
     case TAKE_PARTIAL_SCREENSHOT:
     case TAKE_SCREENSHOT:
     case TAKE_WINDOW_SCREENSHOT:
       return true;
 
 #if defined(OS_CHROMEOS)
     case DEV_ADD_REMOVE_DISPLAY:
     case DEV_TOGGLE_UNIFIED_DESKTOP:
-    case TOGGLE_MIRROR_MODE:
       return debug::DeveloperAcceleratorsEnabled();
 
     case SWAP_PRIMARY_DISPLAY:
       return display::Screen::GetScreen()->GetNumDisplays() > 1;
     case TOUCH_HUD_CLEAR:
     case TOUCH_HUD_MODE_CHANGE:
       return CanHandleTouchHud();
 
     // Following are always enabled.
     case LOCK_PRESSED:
     case LOCK_RELEASED:
     case POWER_PRESSED:
     case POWER_RELEASED:
+    case TOGGLE_MIRROR_MODE:
     case TOUCH_HUD_PROJECTION_TOGGLE:
       return true;
 #endif
 
     default:
       NOTREACHED();
       break;
   }
   return false;
 }
@@ skipping 116 matching lines @@
           message_center::NotifierId(
               message_center::NotifierId::SYSTEM_COMPONENT,
               system_notifier::kNotifierDeprecatedAccelerator),
           message_center::RichNotificationData(),
           new DeprecatedAcceleratorNotificationDelegate));
   message_center::MessageCenter::Get()->AddNotification(
       std::move(notification));
 }
 
 }  // namespace ash