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/. */

 [Pref="dom.sysmsg.enabled",

  JSImplementation="@mozilla.org/dom/activities/request-handler;1",

  ChromeConstructor(DOMString id, optional ActivityOptions options),

  ChromeOnly]

 interface ActivityRequestHandler

 {

     void postResult(any result);

     void postError(DOMString error);

     [Pure, Cached, Frozen]

     readonly attribute ActivityOptions source;

 };