text: // Copyright 2014 Google Inc. All rights reserved
  //
  // Use of this source code is governed by a BSD-style
  // license that can be found in the LICENSE file or at
  // https://developers.google.com/open-source/licenses/bsd
  
  /**
   * @fileoverview U2F message types.
   */
  'use strict';
  
  /**
   * Message types for messsages to/from the extension
   * @const
   * @enum {string}
   */
  var MessageTypes = {
    U2F_REGISTER_REQUEST: 'u2f_register_request',
    U2F_SIGN_REQUEST: 'u2f_sign_request',
    U2F_REGISTER_RESPONSE: 'u2f_register_response',
    U2F_SIGN_RESPONSE: 'u2f_sign_response'
  };
  