js: Add JSDoc to exported functions and fix incorrect JSDoc formatting

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1499>

js/ui/status/keyboard.js

@@ -799,6 +799,9 @@ var InputSourceManager = class extends Signals.EventEmitter {
 
 let _inputSourceManager = null;
 
+/**
+ * @returns {InputSourceManager}
+ */
 function getInputSourceManager() {
     if (_inputSourceManager == null)
         _inputSourceManager = new InputSourceManager();

js/ui/status/location.js

@@ -22,6 +22,7 @@ const ENABLED = 'enabled';
 const APP_PERMISSIONS_TABLE = 'location';
 const APP_PERMISSIONS_ID = 'location';
 
+/** @enum {number} */
 var GeoclueAccuracyLevel = {
     NONE: 0,
     COUNTRY: 1,

js/ui/status/network.js

@@ -32,6 +32,7 @@ const MAX_VISIBLE_NETWORKS = 8;
 // small optimization, to avoid using [] all the time
 const NM80211Mode = NM['80211Mode'];
 
+/** @enum {number} */
 var PortalHelperResult = {
     CANCELLED: 0,
     COMPLETED: 1,

js/ui/status/rfkill.js

@@ -82,7 +82,11 @@ const RfkillManager = GObject.registerClass({
     }
 });
 
-var _manager;
+let _manager;
+
+/**
+ * @returns {RfkillManager}
+ */
 function getRfkillManager() {
     if (_manager != null)
         return _manager;

js/ui/status/thunderbolt.js

@@ -23,8 +23,7 @@ const BoltDeviceInterface = loadInterfaceXML('org.freedesktop.bolt1.Device');
 
 const BoltDeviceProxy = Gio.DBusProxy.makeProxyWrapper(BoltDeviceInterface);
 
-/*  */
-
+/** @enum {string} */
 var Status = {
     DISCONNECTED: 'disconnected',
     CONNECTING: 'connecting',
@@ -34,16 +33,19 @@ var Status = {
     AUTHORIZED: 'authorized',
 };
 
+/** @enum {string} */
 var Policy = {
     DEFAULT: 'default',
     MANUAL: 'manual',
     AUTO: 'auto',
 };
 
+/** @enum {string} */
 var AuthCtrl = {
     NONE: 'none',
 };
 
+/** @enum {string} */
 var AuthMode = {
     DISABLED: 'disabled',
     ENABLED: 'enabled',