[Code cleanup]Remove webui virtual keyboard code

ui/keyboard/keyboard_ui_handler.h

-// Copyright (c) 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.
-
-#ifndef UI_KEYBOARD_KEYBOARD_UI_HANDLER_H_
-#define UI_KEYBOARD_KEYBOARD_UI_HANDLER_H_
-
-#include "base/basictypes.h"
-#include "base/compiler_specific.h"
-#include "content/public/browser/web_ui_message_handler.h"
-
-namespace keyboard {
-
-// The WebUI handler for chrome://keyboard.  Inserts text into the currently
-// focused TextInputClient.
-class KeyboardUIHandler : public content::WebUIMessageHandler {
- public:
-  KeyboardUIHandler();
-  virtual ~KeyboardUIHandler();
-
- private:
-  // |content::WebUIMessageHandler| implementation:
-  virtual void RegisterMessages() OVERRIDE;
-
-  // Callback for the "insertText" message.
-  void HandleInsertTextMessage(const base::ListValue* args);
-
-  // Callback for the "getInputContext" message. The first element in
-  // |args| should be an integer representing request ID.
-  void HandleGetInputContextMessage(const base::ListValue* args);
-
-  // Callback for the "sendKeyEvent" message. The first element in |args| is a
-  // dictionary containing an event type, the character being pressed or
-  // released, a virtual key code, and the state of the shift key.
-  void HandleSendKeyEventMessage(const base::ListValue* args);
-
-  // Callback for the "hideKeyboard" message.
-  void HandleHideKeyboard(const base::ListValue* args);
-
-  DISALLOW_COPY_AND_ASSIGN(KeyboardUIHandler);
-};
-
-}  // namespace keyboard
-
-#endif  // UI_KEYBOARD_KEYBOARD_UI_HANDLER_H_