Bug 1201232 - Use Services.intl for Intl.* APIs in Gecko. r=Paolo,Pike

It's a minor change that should align us better with our selection of locales
(Services.intl will use user selection of regional preference locales).
I also removed the western arabic numeral system limitation to allow persian locales
to use eastern arabic numerals correctly.

MozReview-Commit-ID: 8TXX0X9RY9z

--HG--
extra : rebase_source : a7c8f507d841945e47f2d4cc142b4b05bbfab08f

toolkit/components/narrate/NarrateControls.jsm

@@ -165,8 +165,7 @@ NarrateControls.prototype = {
       let win = this._win;
       let voicePrefs = this._getVoicePref();
       let selectedVoice = voicePrefs[language || "default"];
-      let comparer = win.Intl ?
-        (new Intl.Collator()).compare : (a, b) => a.localeCompare(b);
+      let comparer = (new Services.intl.Collator()).compare;
       let filter = !Services.prefs.getBoolPref("narrate.filter-voices");
       let options = win.speechSynthesis.getVoices().filter(v => {
         return filter || !language || v.lang.split("-")[0] == language;

toolkit/mozapps/downloads/DownloadUtils.jsm

@@ -51,17 +51,13 @@ const MS_PER_DAY = 24 * 60 * 60 * 1000;
 
 var localeNumberFormatCache = new Map();
 function getLocaleNumberFormat(fractionDigits) {
-  // Backward compatibility: don't use localized digits
-  let locale = Intl.NumberFormat().resolvedOptions().locale +
-               "-u-nu-latn";
-  let key = locale + "_" + fractionDigits;
-  if (!localeNumberFormatCache.has(key)) {
-    localeNumberFormatCache.set(key,
-      Intl.NumberFormat(locale,
+  if (!localeNumberFormatCache.has(fractionDigits)) {
+    localeNumberFormatCache.set(fractionDigits,
+      new Services.intl.NumberFormat(undefined,
                         { maximumFractionDigits: fractionDigits,
                           minimumFractionDigits: fractionDigits }));
   }
-  return localeNumberFormatCache.get(key);
+  return localeNumberFormatCache.get(fractionDigits);
 }
 
 const kDownloadProperties =