diff -r 000000000000 -r 6474c204b198 chrome/test/unit/test_bug519468.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/chrome/test/unit/test_bug519468.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,115 @@
+/* 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/.
+ */
+
+var MANIFESTS = [
+  do_get_file("data/test_bug519468.manifest")
+];
+
+// Stub in the locale service so we can control what gets returned as the OS locale setting
+Components.utils.import("resource://gre/modules/XPCOMUtils.jsm");
+
+let stubOSLocale = null;
+
+stubID = Components.ID("9d09d686-d913-414c-a1e6-4be8652d7d93");
+localeContractID = "@mozilla.org/intl/nslocaleservice;1";
+
+StubLocaleService = {
+  classDescription: "Stub version of Locale service for testing",
+  classID:          stubID,
+  contractID:       localeContractID,
+  QueryInterface:   XPCOMUtils.generateQI([Ci.nsILocaleService, Ci.nsISupports, Ci.nsIFactory]),
+
+  createInstance: function (outer, iid) {
+    if (outer)
+      throw Components.results.NS_ERROR_NO_AGGREGATION;
+    return this.QueryInterface(iid);
+  },
+  lockFactory: function (lock) {
+    throw Components.results.NS_ERROR_NOT_IMPLEMENTED;
+  },
+
+  getLocaleComponentForUserAgent: function SLS_getLocaleComponentForUserAgent()
+  {
+    return stubOSLocale;
+  }
+}
+
+let registrar = Components.manager.nsIComponentRegistrar;
+// Save original factory.
+let localeCID = registrar.contractIDToCID(localeContractID)
+let originalFactory =
+      Components.manager.getClassObject(Components.classes[localeContractID],
+                                        Components.interfaces.nsIFactory);
+
+registrar.registerFactory(stubID, "Unit test Locale Service", localeContractID, StubLocaleService);
+
+// Now fire up the test
+do_test_pending()
+registerManifests(MANIFESTS);
+
+var chromeReg = Cc["@mozilla.org/chrome/chrome-registry;1"]
+                .getService(Ci.nsIXULChromeRegistry)
+                .QueryInterface(Ci.nsIToolkitChromeRegistry);
+chromeReg.checkForNewChrome();
+
+var prefService = Cc["@mozilla.org/preferences-service;1"]
+                  .getService(Ci.nsIPrefService)
+                  .QueryInterface(Ci.nsIPrefBranch);
+var os = Cc["@mozilla.org/observer-service;1"]
+         .getService(Ci.nsIObserverService);
+
+var testsLocale = [
+  // These tests cover when the OS local is included in our manifest
+  {matchOS: false, selected: "en-US", osLocale: "xx-AA", locale: "en-US"},
+  {matchOS: true, selected: "en-US", osLocale: "xx-AA", locale: "xx-AA"},
+  {matchOS: false, selected: "fr-FR", osLocale: "xx-AA", locale: "fr-FR"},
+  {matchOS: true, selected: "fr-FR", osLocale: "xx-AA", locale: "xx-AA"},
+  {matchOS: false, selected: "de-DE", osLocale: "xx-AA", locale: "de-DE"},
+  {matchOS: true, selected: "de-DE", osLocale: "xx-AA", locale: "xx-AA"},
+  // these tests cover the case where the OS locale is not available in our manifest, but the
+  // base language is (ie, substitute xx-AA which we have for xx-BB which we don't)
+  {matchOS: false, selected: "en-US", osLocale: "xx-BB", locale: "en-US"},
+  {matchOS: true, selected: "en-US", osLocale: "xx-BB", locale: "xx-AA"},
+  {matchOS: false, selected: "fr-FR", osLocale: "xx-BB", locale: "fr-FR"},
+  {matchOS: true, selected: "fr-FR", osLocale: "xx-BB", locale: "xx-AA"},
+  // These tests cover where the language is not available
+  {matchOS: false, selected: "en-US", osLocale: "xy-BB", locale: "en-US"},
+  {matchOS: true, selected: "en-US", osLocale: "xy-BB", locale: "en-US"},
+  {matchOS: false, selected: "fr-FR", osLocale: "xy-BB", locale: "fr-FR"},
+  {matchOS: true, selected: "fr-FR", osLocale: "xy-BB", locale: "en-US"},
+];
+
+var observedLocale = null;
+
+function test_locale(aTest) {
+  observedLocale = null;
+
+  stubOSLocale = aTest.osLocale;
+  prefService.setBoolPref("intl.locale.matchOS", aTest.matchOS);
+  prefService.setCharPref("general.useragent.locale", aTest.selected);
+
+  chromeReg.reloadChrome();
+
+  do_check_eq(observedLocale, aTest.locale);
+}
+
+// Callback function for observing locale change. May be called more than once
+// per test iteration.
+function checkValidity() {
+  observedLocale = chromeReg.getSelectedLocale("testmatchos");
+  dump("checkValidity called back with locale = " + observedLocale + "\n");
+}
+
+function run_test() {
+  os.addObserver(checkValidity, "selected-locale-has-changed", false);
+
+  for (let count = 0 ; count < testsLocale.length ; count++) {
+    dump("count = " + count + " " + testsLocale[count].toSource() + "\n");
+    test_locale(testsLocale[count]);
+  }
+
+  os.removeObserver(checkValidity, "selected-locale-has-changed");
+  do_test_finished();
+}