appease the linter overlords

lib/browser/api/menu.js

@@ -99,7 +99,6 @@ Menu.prototype.getMenuItemById = function (id) {
   return found
 }
 
-//cleaned up
 Menu.prototype.append = function (item) {
   return this.insert(this.getItemCount(), item)
 }
@@ -268,7 +267,10 @@ function indexToInsertByPosition (items, position) {
 
   // compute new index based on query
   const queries = {
-    'after': (index) => index += 1,
+    'after': (index) => {
+      index += 1
+      return index
+    },
     'endof': (index) => {
       if (index === -1) {
         items.push({id, type: 'separator'})
@@ -285,4 +287,4 @@ function indexToInsertByPosition (items, position) {
   return (query in queries) ? queries[query](idx) : idx
 }
 
-module.exports = Menu
+module.exports = Menu