Use parentheses in IFFE's as per AirBnb styleguide.

app/assets/javascripts/profile/profile.js.es6

-(global => {
+((global) => {
+
   class Profile {
     constructor(opts = {}) {
       this.onSubmitForm = this.onSubmitForm.bind(this);

app/assets/javascripts/search_autocomplete.js.es6

-(global => {
+((global) => {
   const KEYCODE = {
     ESCAPE: 27,

app/assets/javascripts/todos.js.es6

-(global => {
+((global) => {
   class Todos {
     constructor(opts = {}) {

app/assets/javascripts/user.js.es6

-(global => {
+((global) => {
   global.User = class {
     constructor(opts) {
       this.opts = opts;

app/assets/javascripts/user_tabs.js.es6

@@ -57,7 +57,7 @@ content on the Users#show page.
      </div>
    </div>
 */
-(global => {
+((global) => {
   class UserTabs {
     constructor (opts) {
       this.loaded = {};