The Tor Browser / file revision

 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this

  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

 "use strict";

 Components.utils.import("resource://gre/modules/devtools/event-emitter.js");

 const EXPORTED_SYMBOLS = ["Simulator"];

 const Simulator = {

   _simulators: {},

   register: function (version, simulator) {

     this._simulators[version] = simulator;

     this.emit("register");

   },

   unregister: function (version) {

     delete this._simulators[version];

     this.emit("unregister");

   },

   availableVersions: function () {

     return Object.keys(this._simulators).sort();

   },

   getByVersion: function (version) {

     return this._simulators[version];

   }

 };

 EventEmitter.decorate(Simulator);