The Tor Browser: toolkit/mozapps/extensions/test/browser/browser_experiments.js@6474c204b198 (annotated)

toolkit/mozapps/extensions/test/browser/browser_experiments.js@6474c204b198 (annotated)

toolkit/mozapps/extensions/test/browser/browser_experiments.js

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* Any copyright is dedicated to the Public Domain.
  * http://creativecommons.org/publicdomain/zero/1.0/
  */
 let {AddonTestUtils} = Components.utils.import("resource://testing-common/AddonManagerTesting.jsm", {});
 let {HttpServer} = Components.utils.import("resource://testing-common/httpd.js", {});
 let gManagerWindow;
 let gCategoryUtilities;
 let gExperiments;
 let gHttpServer;
 let gSavedManifestURI;
 let gIsEnUsLocale;
 const SEC_IN_ONE_DAY = 24 * 60 * 60;
 const MS_IN_ONE_DAY  = SEC_IN_ONE_DAY * 1000;
 function getExperimentAddons() {
   let deferred = Promise.defer();
   AddonManager.getAddonsByTypes(["experiment"], (addons) => {
     deferred.resolve(addons);
   });
   return deferred.promise;
 }
 function getInstallItem() {
   let doc = gManagerWindow.document;
   let view = doc.getElementById("view-port").selectedPanel;
   let list = doc.getElementById("addon-list");
   let node = list.firstChild;
   while (node) {
     if (node.getAttribute("status") == "installing") {
       return node;
     }
     node = node.nextSibling;
   }
   return null;
 }
 function patchPolicy(policy, data) {
   for (let key of Object.keys(data)) {
     Object.defineProperty(policy, key, {
       value: data[key],
       writable: true,
     });
   }
 }
 function defineNow(policy, time) {
   patchPolicy(policy, { now: () => new Date(time) });
 }
 function openDetailsView(aId) {
   let item = get_addon_element(gManagerWindow, aId);
   Assert.ok(item, "Should have got add-on element.");
   is_element_visible(item, "Add-on element should be visible.");
   EventUtils.synthesizeMouseAtCenter(item, { clickCount: 1 }, gManagerWindow);
   EventUtils.synthesizeMouseAtCenter(item, { clickCount: 2 }, gManagerWindow);
   let deferred = Promise.defer();
   wait_for_view_load(gManagerWindow, deferred.resolve);
   return deferred.promise;
 }
 function clickRemoveButton(addonElement) {
   let btn = gManagerWindow.document.getAnonymousElementByAttribute(addonElement, "anonid", "remove-btn");
   if (!btn) {
     return Promise.reject();
   }
   EventUtils.synthesizeMouseAtCenter(btn, { clickCount: 1 }, gManagerWindow);
   let deferred = Promise.defer();
   setTimeout(deferred.resolve, 0);
   return deferred;
 }
 function clickUndoButton(addonElement) {
   let btn = gManagerWindow.document.getAnonymousElementByAttribute(addonElement, "anonid", "undo-btn");
   if (!btn) {
     return Promise.reject();
   }
   EventUtils.synthesizeMouseAtCenter(btn, { clickCount: 1 }, gManagerWindow);
   let deferred = Promise.defer();
   setTimeout(deferred.resolve, 0);
   return deferred;
 }
 add_task(function* initializeState() {
   gManagerWindow = yield open_manager();
   gCategoryUtilities = new CategoryUtilities(gManagerWindow);
   registerCleanupFunction(() => {
     Services.prefs.clearUserPref("experiments.enabled");
     if (gHttpServer) {
       gHttpServer.stop(() => {});
       Services.prefs.clearUserPref("experiments.manifest.cert.checkAttributes");
       if (gSavedManifestURI !== undefined) {
         Services.prefs.setCharPref("experments.manifest.uri", gSavedManifestURI);
       }
     }
     if (gExperiments) {
       let tmp = {};
       Cu.import("resource:///modules/experiments/Experiments.jsm", tmp);
       gExperiments._policy = new tmp.Experiments.Policy();
     }
   });
   let chrome = Cc["@mozilla.org/chrome/chrome-registry;1"].getService(Ci.nsIXULChromeRegistry);
   gIsEnUsLocale = chrome.getSelectedLocale("global") == "en-US";
   // The Experiments Manager will interfere with us by preventing installs
   // of experiments it doesn't know about. We remove it from the equation
   // because here we are only concerned with core Addon Manager operation,
   // not the superset Experiments Manager has imposed.
   if ("@mozilla.org/browser/experiments-service;1" in Components.classes) {
     let tmp = {};
     Cu.import("resource:///modules/experiments/Experiments.jsm", tmp);
     // There is a race condition between XPCOM service initialization and
     // this test running. We have to initialize the instance first, then
     // uninitialize it to prevent this.
     gExperiments = tmp.Experiments.instance();
     yield gExperiments._mainTask;
     yield gExperiments.uninit();
   }
 });
 // On an empty profile with no experiments, the experiment category
 // should be hidden.
 add_task(function* testInitialState() {
   Assert.ok(gCategoryUtilities.get("experiment", false), "Experiment tab is defined.");
   Assert.ok(!gCategoryUtilities.isTypeVisible("experiment"), "Experiment tab hidden by default.");
 });
 add_task(function* testExperimentInfoNotVisible() {
   yield gCategoryUtilities.openType("extension");
   let el = gManagerWindow.document.getElementsByClassName("experiment-info-container")[0];
   is_element_hidden(el, "Experiment info not visible on other types.");
 });
 // If we have an active experiment, we should see the experiments tab
 // and that tab should have some messages.
 add_task(function* testActiveExperiment() {
   let addon = yield install_addon("addons/browser_experiment1.xpi");
   Assert.ok(addon.userDisabled, "Add-on is disabled upon initial install.");
   Assert.equal(addon.isActive, false, "Add-on is not active.");
   Assert.ok(gCategoryUtilities.isTypeVisible("experiment"), "Experiment tab visible.");
   yield gCategoryUtilities.openType("experiment");
   let el = gManagerWindow.document.getElementsByClassName("experiment-info-container")[0];
   is_element_visible(el, "Experiment info is visible on experiment tab.");
 });
 add_task(function* testExperimentLearnMore() {
   // Actual URL is irrelevant.
   Services.prefs.setCharPref("toolkit.telemetry.infoURL",
                              "http://mochi.test:8888/server.js");
   yield gCategoryUtilities.openType("experiment");
   let btn = gManagerWindow.document.getElementById("experiments-learn-more");
   if (!gUseInContentUI) {
     is_element_hidden(btn, "Learn more button hidden if not using in-content UI.");
     Services.prefs.clearUserPref("toolkit.telemetry.infoURL");
     return;
   }
   is_element_visible(btn, "Learn more button visible.");
   let deferred = Promise.defer();
   window.addEventListener("DOMContentLoaded", function onLoad(event) {
     info("Telemetry privacy policy window opened.");
     window.removeEventListener("DOMContentLoaded", onLoad, false);
     let browser = gBrowser.selectedTab.linkedBrowser;
     let expected = Services.prefs.getCharPref("toolkit.telemetry.infoURL");
     Assert.equal(browser.currentURI.spec, expected, "New tab should have loaded privacy policy.");
     browser.contentWindow.close();
     Services.prefs.clearUserPref("toolkit.telemetry.infoURL");
     deferred.resolve();
   }, false);
   info("Opening telemetry privacy policy.");
   EventUtils.synthesizeMouseAtCenter(btn, {}, gManagerWindow);
   yield deferred.promise;
 });
 add_task(function* testOpenPreferences() {
   yield gCategoryUtilities.openType("experiment");
   let btn = gManagerWindow.document.getElementById("experiments-change-telemetry");
   if (!gUseInContentUI) {
     is_element_hidden(btn, "Change telemetry button not enabled in out of window UI.");
     info("Skipping preferences open test because not using in-content UI.");
     return;
   }
   is_element_visible(btn, "Change telemetry button visible in in-content UI.");
   let deferred = Promise.defer();
   Services.obs.addObserver(function observer(prefWin, topic, data) {
     Services.obs.removeObserver(observer, "advanced-pane-loaded");
     info("Advanced preference pane opened.");
     // We want this test to fail if the preferences pane changes.
     let el = prefWin.document.getElementById("dataChoicesPanel");
     is_element_visible(el);
     prefWin.close();
     info("Closed preferences pane.");
     deferred.resolve();
   }, "advanced-pane-loaded", false);
   info("Loading preferences pane.");
   EventUtils.synthesizeMouseAtCenter(btn, {}, gManagerWindow);
   yield deferred.promise;
 });
 add_task(function* testButtonPresence() {
   yield gCategoryUtilities.openType("experiment");
   let item = get_addon_element(gManagerWindow, "test-experiment1@experiments.mozilla.org");
   Assert.ok(item, "Got add-on element.");
   item.parentNode.ensureElementIsVisible(item);
   let el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "remove-btn");
   // Corresponds to the uninstall permission.
   is_element_visible(el, "Remove button is visible.");
   // Corresponds to lack of disable permission.
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "disable-btn");
   is_element_hidden(el, "Disable button not visible.");
   // Corresponds to lack of enable permission.
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "enable-btn");
   is_element_hidden(el, "Enable button not visible.");
 });
 // Remove the add-on we've been testing with.
 add_task(function* testCleanup() {
   yield AddonTestUtils.uninstallAddonByID("test-experiment1@experiments.mozilla.org");
   // Verify some conditions, just in case.
   let addons = yield getExperimentAddons();
   Assert.equal(addons.length, 0, "No experiment add-ons are installed.");
 });
 // The following tests should ideally live in browser/experiments/. However,
 // they rely on some of the helper functions from head.js, which can't easily
 // be consumed from other directories. So, they live here.
 add_task(function* testActivateExperiment() {
   if (!gExperiments) {
     info("Skipping experiments test because that feature isn't available.");
     return;
   }
   gHttpServer = new HttpServer();
   gHttpServer.start(-1);
   let root = "http://localhost:" + gHttpServer.identity.primaryPort + "/";
   gHttpServer.registerPathHandler("/manifest", (request, response) => {
     response.setStatusLine(null, 200, "OK");
     response.write(JSON.stringify({
       "version": 1,
       "experiments": [
         {
           id: "experiment-1",
           xpiURL: TESTROOT + "addons/browser_experiment1.xpi",
           xpiHash: "IRRELEVANT",
           startTime: Date.now() / 1000 - 3600,
           endTime: Date.now() / 1000 + 3600,
           maxActiveSeconds: 600,
           appName: [Services.appinfo.name],
           channel: [gExperiments._policy.updatechannel()],
         },
       ],
     }));
     response.processAsync();
     response.finish();
   });
   Services.prefs.setBoolPref("experiments.manifest.cert.checkAttributes", false);
   gSavedManifestURI = Services.prefs.getCharPref("experiments.manifest.uri");
   Services.prefs.setCharPref("experiments.manifest.uri", root + "manifest");
   // We need to remove the cache file to help ensure consistent state.
   yield OS.File.remove(gExperiments._cacheFilePath);
   Services.prefs.setBoolPref("experiments.enabled", true);
   info("Initializing experiments service.");
   yield gExperiments.init();
   info("Experiments service finished first run.");
   // Check conditions, just to be sure.
   let experiments = yield gExperiments.getExperiments();
   Assert.equal(experiments.length, 0, "No experiments known to the service.");
   // This makes testing easier.
   gExperiments._policy.ignoreHashes = true;
   info("Manually updating experiments manifest.");
   yield gExperiments.updateManifest();
   info("Experiments update complete.");
   let deferred = Promise.defer();
   gHttpServer.stop(() => {
     gHttpServer = null;
     info("getting experiment by ID");
     AddonManager.getAddonByID("test-experiment1@experiments.mozilla.org", (addon) => {
       Assert.ok(addon, "Add-on installed via Experiments manager.");
       deferred.resolve();
     });
   });
   yield deferred.promise;
   Assert.ok(gCategoryUtilities.isTypeVisible, "experiment", "Experiment tab visible.");
   yield gCategoryUtilities.openType("experiment");
   let el = gManagerWindow.document.getElementsByClassName("experiment-info-container")[0];
   is_element_visible(el, "Experiment info is visible on experiment tab.");
 });
 add_task(function testDeactivateExperiment() {
   if (!gExperiments) {
     return;
   }
   // Fake an empty manifest to purge data from previous manifest.
   yield gExperiments._updateExperiments({
     "version": 1,
     "experiments": [],
   });
   yield gExperiments.disableExperiment("testing");
   // We should have a record of the previously-active experiment.
   let experiments = yield gExperiments.getExperiments();
   Assert.equal(experiments.length, 1, "1 experiment is known.");
   Assert.equal(experiments[0].active, false, "Experiment is not active.");
   // We should have a previous experiment in the add-ons manager.
   let deferred = Promise.defer();
   AddonManager.getAddonsByTypes(["experiment"], (addons) => {
     deferred.resolve(addons);
   });
   let addons = yield deferred.promise;
   Assert.equal(addons.length, 1, "1 experiment add-on known.");
   Assert.ok(addons[0].appDisabled, "It is a previous experiment.");
   Assert.equal(addons[0].id, "experiment-1", "Add-on ID matches expected.");
   // Verify the UI looks sane.
   Assert.ok(gCategoryUtilities.isTypeVisible("experiment"), "Experiment tab visible.");
   let item = get_addon_element(gManagerWindow, "experiment-1");
   Assert.ok(item, "Got add-on element.");
   Assert.ok(!item.active, "Element should not be active.");
   item.parentNode.ensureElementIsVisible(item);
   // User control buttons should not be present because previous experiments
   // should have no permissions.
   let el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "remove-btn");
   is_element_hidden(el, "Remove button is not visible.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "disable-btn");
   is_element_hidden(el, "Disable button is not visible.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "enable-btn");
   is_element_hidden(el, "Enable button is not visible.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "preferences-btn");
   is_element_hidden(el, "Preferences button is not visible.");
 });
 add_task(function testActivateRealExperiments() {
   if (!gExperiments) {
     info("Skipping experiments test because that feature isn't available.");
     return;
   }
   yield gExperiments._updateExperiments({
     "version": 1,
     "experiments": [
       {
         id: "experiment-2",
         xpiURL: TESTROOT + "addons/browser_experiment1.xpi",
         xpiHash: "IRRELEVANT",
         startTime: Date.now() / 1000 - 3600,
         endTime: Date.now() / 1000 + 3600,
         maxActiveSeconds: 600,
         appName: [Services.appinfo.name],
         channel: [gExperiments._policy.updatechannel()],
       },
     ],
   });
   yield gExperiments._run();
   // Check the active experiment.
   let item = get_addon_element(gManagerWindow, "test-experiment1@experiments.mozilla.org");
   Assert.ok(item, "Got add-on element.");
   item.parentNode.ensureElementIsVisible(item);
   let el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "experiment-state");
   is_element_visible(el, "Experiment state label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "Active");
   }
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "experiment-time");
   is_element_visible(el, "Experiment time label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "Less than a day remaining");
   }
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "error-container");
   is_element_hidden(el, "error-container should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "warning-container");
   is_element_hidden(el, "warning-container should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "pending-container");
   is_element_hidden(el, "pending-container should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "version");
   is_element_hidden(el, "version should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "class", "disabled-postfix");
   is_element_hidden(el, "disabled-postfix should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "class", "update-postfix");
   is_element_hidden(el, "update-postfix should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "class", "experiment-bullet");
   is_element_visible(el, "experiment-bullet should be visible.");
   // Check the previous experiment.
   item = get_addon_element(gManagerWindow, "experiment-1");
   Assert.ok(item, "Got add-on element.");
   item.parentNode.ensureElementIsVisible(item);
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "experiment-state");
   is_element_visible(el, "Experiment state label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "Complete");
   }
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "experiment-time");
   is_element_visible(el, "Experiment time label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "Less than a day ago");
   }
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "error-container");
   is_element_hidden(el, "error-container should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "warning-container");
   is_element_hidden(el, "warning-container should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "pending-container");
   is_element_hidden(el, "pending-container should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "version");
   is_element_hidden(el, "version should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "class", "disabled-postfix");
   is_element_hidden(el, "disabled-postfix should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "class", "update-postfix");
   is_element_hidden(el, "update-postfix should be hidden.");
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "class", "experiment-bullet");
   is_element_visible(el, "experiment-bullet should be visible.");
   // Install an "older" experiment.
   yield gExperiments.disableExperiment("experiment-2");
   let now = Date.now();
   let fakeNow = now - 5 * MS_IN_ONE_DAY;
   defineNow(gExperiments._policy, fakeNow);
   yield gExperiments._updateExperiments({
     "version": 1,
     "experiments": [
       {
         id: "experiment-3",
         xpiURL: TESTROOT + "addons/browser_experiment1.xpi",
         xpiHash: "IRRELEVANT",
         startTime: fakeNow / 1000 - SEC_IN_ONE_DAY,
         endTime: now / 1000 + 10 * SEC_IN_ONE_DAY,
         maxActiveSeconds: 100 * SEC_IN_ONE_DAY,
         appName: [Services.appinfo.name],
         channel: [gExperiments._policy.updatechannel()],
       },
     ],
   });
   yield gExperiments._run();
   // Check the active experiment.
   item = get_addon_element(gManagerWindow, "test-experiment1@experiments.mozilla.org");
   Assert.ok(item, "Got add-on element.");
   item.parentNode.ensureElementIsVisible(item);
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "experiment-state");
   is_element_visible(el, "Experiment state label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "Active");
   }
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "experiment-time");
   is_element_visible(el, "Experiment time label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "10 days remaining");
   }
   // Disable it and check it's previous experiment entry.
   yield gExperiments.disableExperiment("experiment-3");
   item = get_addon_element(gManagerWindow, "experiment-3");
   Assert.ok(item, "Got add-on element.");
   item.parentNode.ensureElementIsVisible(item);
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "experiment-state");
   is_element_visible(el, "Experiment state label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "Complete");
   }
   el = item.ownerDocument.getAnonymousElementByAttribute(item, "anonid", "experiment-time");
   is_element_visible(el, "Experiment time label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "5 days ago");
   }
 });
 add_task(function testDetailView() {
   if (!gExperiments) {
     info("Skipping experiments test because that feature isn't available.");
     return;
   }
   defineNow(gExperiments._policy, Date.now());
   yield gExperiments._updateExperiments({
     "version": 1,
     "experiments": [
       {
         id: "experiment-4",
         xpiURL: TESTROOT + "addons/browser_experiment1.xpi",
         xpiHash: "IRRELEVANT",
         startTime: Date.now() / 1000 - 3600,
         endTime: Date.now() / 1000 + 3600,
         maxActiveSeconds: 600,
         appName: [Services.appinfo.name],
         channel: [gExperiments._policy.updatechannel()],
       },
     ],
   });
   yield gExperiments._run();
   // Check active experiment.
   yield openDetailsView("test-experiment1@experiments.mozilla.org");
   let el = gManagerWindow.document.getElementById("detail-experiment-state");
   is_element_visible(el, "Experiment state label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "Active");
   }
   el = gManagerWindow.document.getElementById("detail-experiment-time");
   is_element_visible(el, "Experiment time label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "Less than a day remaining");
   }
   el = gManagerWindow.document.getElementById("detail-version");
   is_element_hidden(el, "detail-version should be hidden.");
   el = gManagerWindow.document.getElementById("detail-creator");
   is_element_hidden(el, "detail-creator should be hidden.");
   el = gManagerWindow.document.getElementById("detail-experiment-bullet");
   is_element_visible(el, "experiment-bullet should be visible.");
   // Check previous experiment.
   yield gCategoryUtilities.openType("experiment");
   yield openDetailsView("experiment-3");
   let el = gManagerWindow.document.getElementById("detail-experiment-state");
   is_element_visible(el, "Experiment state label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "Complete");
   }
   el = gManagerWindow.document.getElementById("detail-experiment-time");
   is_element_visible(el, "Experiment time label should be visible.");
   if (gIsEnUsLocale) {
     Assert.equal(el.value, "5 days ago");
   }
   el = gManagerWindow.document.getElementById("detail-version");
   is_element_hidden(el, "detail-version should be hidden.");
   el = gManagerWindow.document.getElementById("detail-creator");
   is_element_hidden(el, "detail-creator should be hidden.");
   el = gManagerWindow.document.getElementById("detail-experiment-bullet");
   is_element_visible(el, "experiment-bullet should be visible.");
 });
 add_task(function* testRemoveAndUndo() {
   if (!gExperiments) {
     info("Skipping experiments test because that feature isn't available.");
     return;
   }
   yield gCategoryUtilities.openType("experiment");
   let addon = get_addon_element(gManagerWindow, "test-experiment1@experiments.mozilla.org");
   Assert.ok(addon, "Got add-on element.");
   yield clickRemoveButton(addon);
   addon.parentNode.ensureElementIsVisible(addon);
   let el = gManagerWindow.document.getAnonymousElementByAttribute(addon, "class", "pending");
   is_element_visible(el, "Uninstall undo information should be visible.");
   yield clickUndoButton(addon);
   addon = get_addon_element(gManagerWindow, "test-experiment1@experiments.mozilla.org");
   Assert.ok(addon, "Got add-on element.");
 });
 add_task(function* testCleanup() {
   if (gExperiments) {
     Services.prefs.clearUserPref("experiments.enabled");
     Services.prefs.clearUserPref("experiments.manifest.cert.checkAttributes");
     Services.prefs.setCharPref("experiments.manifest.uri", gSavedManifestURI);
     // We perform the uninit/init cycle to purge any leftover state.
     yield OS.File.remove(gExperiments._cacheFilePath);
     yield gExperiments.uninit();
     yield gExperiments.init();
   }
   // Check post-conditions.
   let addons = yield getExperimentAddons();
   Assert.equal(addons.length, 0, "No experiment add-ons are installed.");
   yield close_manager(gManagerWindow);
 });