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/. */

 const nsIQuotaManager = Components.interfaces.nsIQuotaManager;

 let gURI = Components.classes["@mozilla.org/network/io-service;1"].getService(Components.interfaces.nsIIOService).newURI("http://localhost", null, null);

 function onUsageCallback(uri, usage, fileUsage) {}

 function onLoad()

 {

   var quotaManager = Components.classes["@mozilla.org/dom/quota/manager;1"]

                                .getService(nsIQuotaManager);

   var quotaRequest = quotaManager.getUsageForURI(gURI, onUsageCallback);

   quotaRequest.cancel();

   Components.classes["@mozilla.org/observer-service;1"]

             .getService(Components.interfaces.nsIObserverService)

             .notifyObservers(window, "bug839193-loaded", null);

 }

 function onUnload()

 {

   Components.classes["@mozilla.org/observer-service;1"]

             .getService(Components.interfaces.nsIObserverService)

             .notifyObservers(window, "bug839193-unloaded", null);

 }