The Tor Browser / file revision

 function test() {

   waitForExplicitFinish();

   // Setup a phony handler to ensure the app pane will be populated.

   var handler = Cc["@mozilla.org/uriloader/web-handler-app;1"].

                 createInstance(Ci.nsIWebHandlerApp);

   handler.name = "App pane alive test";

   handler.uriTemplate = "http://test.mozilla.org/%s";

   var extps = Cc["@mozilla.org/uriloader/external-protocol-service;1"].

               getService(Ci.nsIExternalProtocolService);

   var info = extps.getProtocolHandlerInfo("apppanetest");

   info.possibleApplicationHandlers.appendElement(handler, false);

   var hserv = Cc["@mozilla.org/uriloader/handler-service;1"].

               getService(Ci.nsIHandlerService);

   hserv.store(info);

   function observer(win, topic, data) {

     if (topic != "app-handler-pane-loaded")

       return;

     Services.obs.removeObserver(observer, "app-handler-pane-loaded");

     runTest(win);

   }

   Services.obs.addObserver(observer, "app-handler-pane-loaded", false);

   openDialog("chrome://browser/content/preferences/preferences.xul", "Preferences",

              "chrome,titlebar,toolbar,centerscreen,dialog=no", "paneApplications");

 }

 function runTest(win) {

   var sel = win.document.documentElement.getAttribute("lastSelected");

   ok(sel == "paneApplications", "Specified pane was opened");

   var rbox = win.document.getElementById("handlersView");

   ok(rbox, "handlersView is present");

   var items = rbox && rbox.getElementsByTagName("richlistitem");

   ok(items && items.length > 0, "App handler list populated");

   var handlerAdded = false;

   for (let i = 0; i < items.length; i++) {

     if (items[i].type == "apppanetest")

       handlerAdded = true;

   }

   ok(handlerAdded, "apppanetest protocol handler was successfully added");

   win.close();

   finish();

 }