Remove KeyboardDevice class.

ui/events/devices/device_hotplug_event_observer.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_DEVICES_DEVICE_HOTPLUG_EVENT_OBSERVER_H_
 #define UI_EVENTS_DEVICES_DEVICE_HOTPLUG_EVENT_OBSERVER_H_
 
 #include <vector>
 
 #include "ui/events/devices/events_devices_export.h"
 
 namespace ui {
 
 struct InputDevice;
-struct KeyboardDevice;
 struct TouchscreenDevice;
 
 // Listener for specific input device hotplug events.
 class EVENTS_DEVICES_EXPORT DeviceHotplugEventObserver {
  public:
   virtual ~DeviceHotplugEventObserver() {}
 
   // On a hotplug event this is called with the list of available touchscreen
   // devices. The set of touchscreen devices may not have changed.
   virtual void OnTouchscreenDevicesUpdated(
       const std::vector<TouchscreenDevice>& devices) = 0;
 
   // On a hotplug event this is called with the list of available keyboard
   // devices. The set of keyboard devices may not have changed.
   virtual void OnKeyboardDevicesUpdated(
-      const std::vector<KeyboardDevice>& devices) = 0;
+      const std::vector<InputDevice>& devices) = 0;
 
   // On a hotplug event this is called with the list of available mice. The set
   // of mice may not have changed.
   virtual void OnMouseDevicesUpdated(
       const std::vector<InputDevice>& devices) = 0;
 
   // On a hotplug event this is called with the list of available touchpads. The
   // set of touchpads may not have changed.
   virtual void OnTouchpadDevicesUpdated(
       const std::vector<InputDevice>& devices) = 0;
 
   // On completion of the initial startup scan. This means all of the above
   // OnDevicesUpdated() methods have been called with a complete list.
   virtual void OnDeviceListsComplete() = 0;
 };
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_DEVICES_DEVICE_HOTPLUG_EVENT_OBSERVER_H_