ui: Wait for i18n setup before rendering hotkeys help.

Much like 038a2c769, but for the three tabs at the top of the
`?` help overlay for keyboard shortcuts.

static/js/ui.js

@@ -117,8 +117,7 @@ exports.show_failed_message_success = function (message_id) {
     });
 };
 
-$(document).ready(function () {
-
+function _setup_info_overlay() {
     var info_overlay_toggle = components.toggle({
         name: "info-overlay-toggle",
         selected: 0,
@@ -136,7 +135,7 @@ $(document).ready(function () {
 
     $(".informational-overlays .overlay-tabs")
         .append($(info_overlay_toggle).addClass("large"));
-});
+}
 
 exports.show_info_overlay = function (target) {
     var overlay = $(".informational-overlays");
@@ -271,6 +270,10 @@ $(function () {
     }
 });
 
+exports.initialize = function () {
+    i18n.ensure_i18n(_setup_info_overlay);
+};
+
 return exports;
 }());
 

static/js/ui_init.js

@@ -269,6 +269,7 @@ $(function () {
     drafts.initialize();
     sent_messages.initialize();
     compose.initialize();
+    ui.initialize();
 });