Use ES6 classes

Always use the shorthand notation if the function is a method of an object or class `{ foo() { ... } }` or `class bar { foo() { ... } }`
unless it's a callback in which case you a fat arrow function should be used `{ cb: () => { ... } }`

app/localization.js

@@ -10,17 +10,17 @@
  * Localization Utilities
  */
 
-export function Localizer() {
-    // Currently configured language
-    this.language = 'en';
+export class Localizer {
+    constructor() {
+        // Currently configured language
+        this.language = 'en';
 
-    // Current dictionary of translations
-    this.dictionary = undefined;
-}
+        // Current dictionary of translations
+        this.dictionary = undefined;
+    }
 
-Localizer.prototype = {
     // Configure suitable language based on user preferences
-    setup: function (supportedLanguages) {
+    setup(supportedLanguages) {
         this.language = 'en'; // Default: US English
 
         /*
@@ -78,21 +78,22 @@ Localizer.prototype = {
                 return;
             }
         }
-    },
+    }
 
     // Retrieve localised text
-    get: function (id) {
+    get(id) {
         if (typeof this.dictionary !== 'undefined' && this.dictionary[id]) {
             return this.dictionary[id];
         } else {
             return id;
         }
-    },
+    }
 
     // Traverses the DOM and translates relevant fields
     // See https://html.spec.whatwg.org/multipage/dom.html#attr-translate
-    translateDOM: function () {
+    translateDOM() {
         const self = this;
+
         function process(elem, enabled) {
             function isAnyOf(searchElement, items) {
                 return items.indexOf(searchElement) !== -1;
@@ -160,8 +161,8 @@ Localizer.prototype = {
         }
 
         process(document.body, true);
-    },
-};
+    }
+}
 
 export const l10n = new Localizer();
 export default l10n.get.bind(l10n);