Bug 984274 - Remove WebappsUpdateTimers in B2G mochitests. r=fabrice

b2g/components/test/mochitest/mochitest.ini

@@ -7,7 +7,6 @@ support-files =
   systemapp_helper.js
 
 [test_sandbox_permission.html]
-skip-if = true # bug 984274 - frequent timeouts
 [test_filepicker_path.html]
 [test_permission_deny.html]
 [test_permission_gum_remember.html]

testing/mochitest/b2g_start_script.js

@@ -9,6 +9,8 @@ let wifiSettings = __marionetteParams[3]
 let prefs = Components.classes["@mozilla.org/preferences-service;1"].
                             getService(Components.interfaces.nsIPrefBranch)
 let settings = window.navigator.mozSettings;
+let cm = Components.classes["@mozilla.org/categorymanager;1"].
+                    getService(Components.interfaces.nsICategoryManager);
 
 if (wifiSettings)
   wifiSettings = JSON.parse(wifiSettings);
@@ -20,6 +22,12 @@ const CHILD_LOGGER_SCRIPT = "chrome://specialpowers/content/MozillaLogger.js";
 let homescreen = document.getElementById('systemapp');
 let container = homescreen.contentWindow.document.getElementById('test-container');
 
+// Disable udpate timers which cause failure in b2g permisson prompt tests.
+if (cm) {
+  cm.deleteCategoryEntry("update-timer", "WebappsUpdateTimer", false);
+  cm.deleteCategoryEntry("update-timer", "nsUpdateService", false);
+}
+
 function openWindow(aEvent) {
   var popupIframe = aEvent.detail.frameElement;
   popupIframe.style = 'position: absolute; left: 0; top: 0px; background: white;';