Move all event related devices from ui/events/ to ui/events/devices/

ui/events/x/hotplug_event_handler_x11.h

-// Copyright 2014 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 UI_EVENTS_X_HOTPLUG_EVENT_HANDLER_H_
-#define UI_EVENTS_X_HOTPLUG_EVENT_HANDLER_H_
-
-#include "ui/events/x/device_list_cache_x.h"
-
-namespace ui {
-
-class DeviceHotplugEventObserver;
-
-// Parses X11 native devices and propagates the list of active devices to an
-// observer.
-class EVENTS_BASE_EXPORT HotplugEventHandlerX11 {
- public:
-  explicit HotplugEventHandlerX11(DeviceHotplugEventObserver* delegate);
-  ~HotplugEventHandlerX11();
-
-  // Called on an X11 hotplug event.
-  void OnHotplugEvent();
-
- private:
-  void HandleTouchscreenDevices(const XIDeviceList& device_list);
-  void HandleKeyboardDevices(const XIDeviceList& device_list);
-
-  DeviceHotplugEventObserver* delegate_;  // Not owned.
-
-  DISALLOW_COPY_AND_ASSIGN(HotplugEventHandlerX11);
-};
-
-}  // namespace ui
-
-#endif  // UI_EVENTS_X_HOTPLUG_EVENT_HANDLER_H_