mash: Move accessibility_types.h from ui namespace to ash namespace

ash/common/system/tray/wm_system_tray_notifier.h

 // 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.
 
 #ifndef ASH_COMMON_SYSTEM_TRAY_WM_SYSTEM_TRAY_NOTIFIER_H_
 #define ASH_COMMON_SYSTEM_TRAY_WM_SYSTEM_TRAY_NOTIFIER_H_
 
 #include "ash/ash_export.h"
 #include "ash/common/accessibility_types.h"
 #include "base/macros.h"
@@ skipping 19 matching lines @@
   void AddAccessibilityObserver(AccessibilityObserver* observer);
   void RemoveAccessibilityObserver(AccessibilityObserver* observer);
 
   void AddClockObserver(ClockObserver* observer);
   void RemoveClockObserver(ClockObserver* observer);
 
   void AddUpdateObserver(UpdateObserver* observer);
   void RemoveUpdateObserver(UpdateObserver* observer);
 
   void NotifyAccessibilityModeChanged(
-      ui::AccessibilityNotificationVisibility notify);
+      AccessibilityNotificationVisibility notify);
 
   void NotifyRefreshClock();
   void NotifyDateFormatChanged();
   void NotifySystemClockTimeUpdated();
   void NotifySystemClockCanSetTimeChanged(bool can_set_time);
 
   void NotifyUpdateRecommended(const UpdateInfo& info);
 
  private:
   base::ObserverList<AccessibilityObserver> accessibility_observers_;
   base::ObserverList<ClockObserver> clock_observers_;
   base::ObserverList<UpdateObserver> update_observers_;
 
   DISALLOW_COPY_AND_ASSIGN(WmSystemTrayNotifier);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SYSTEM_TRAY_WM_SYSTEM_TRAY_NOTIFIER_H_