[IME] migrate the xkb ID to extension based xkb ID.

chrome/browser/chromeos/input_method/mock_input_method_manager.cc

 // Copyright (c) 2012 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 "chrome/browser/chromeos/input_method/mock_input_method_manager.h"
 
 namespace chromeos {
 namespace input_method {
 
 MockInputMethodManager::MockInputMethodManager()
@@ skipping 147 matching lines @@
 }
 
 void MockInputMethodManager::set_application_locale(const std::string& value) {
   delegate_.set_active_locale(value);
 }
 
 bool MockInputMethodManager::IsLoginKeyboard(
     const std::string& layout) const {
   return true;
 }
+
+bool MigrateXkbInputMethods(std::vector<std::string>* input_method_ids) {
+  return false;
+}
+
 }  // namespace input_method
 }  // namespace chromeos