Bug 1493711 - Enable langpack download on release and Beta r=jaws

Fix the message bar showing when the "search" option is selected. A value
was added in 597134aa66 for testing but the change handler was expecting
no value to be set for search.

Differential Revision: https://phabricator.services.mozilla.com/D10967

--HG--
extra : moz-landing-system : lando

browser/app/profile/firefox.js

@@ -1748,8 +1748,8 @@ pref("app.shield.optoutstudies.enabled", false);
 
 // Multi-lingual preferences
 pref("intl.multilingual.enabled", false);
-// AMO only serves language packs for release versions, so this feature only works on release.
-#ifdef RELEASE
+// AMO only serves language packs for release and beta versions.
+#ifdef RELEASE_OR_BETA
 pref("intl.multilingual.downloadEnabled", true);
 #else
 pref("intl.multilingual.downloadEnabled", false);

browser/components/preferences/in-content/main.js

@@ -822,9 +822,7 @@ var gMainPane = {
   onBrowserLanguageChange(event) {
     let locale = event.target.value;
 
-    // If there is no value, then this is the search option, leave the
-    // message bar in its current state.
-    if (!locale) {
+    if (locale == "search") {
       return;
     } else if (locale == Services.locale.requestedLocale) {
       this.hideConfirmLanguageChangeMessageBar();

browser/components/preferences/in-content/tests/browser_browser_languages_subdialog.js

@@ -311,6 +311,9 @@ add_task(async function testInstallFromAMO() {
   // Open the dialog.
   let {dialogDoc, available, requested} = await openDialog(doc, true);
 
+  // Make sure the message bar is still hidden.
+  is(messageBar.hidden, true, "The message bar is still hidden after searching");
+
   let dropdown = dialogDoc.getElementById("availableLocales");
   if (dropdown.itemCount == 1) {
     await waitForMutation(