Issue 4795 - Use modern JavaScript syntax

lib/stats.js

Index: lib/stats.js
diff --git a/lib/stats.js b/lib/stats.js
index 81dfff3af0728c3ef5941002c01f055752cdccc3..a8ab3f1d87c6a240c7816a381dc3873661e9c904 100644
--- a/lib/stats.js
+++ b/lib/stats.js
@@ -17,6 +17,8 @@
 
 /** @module stats */
 
+"use strict";
+
 let {Prefs} = require("prefs");
 let {BlockingFilter} = require("filterClasses");
 let {FilterNotifier} = require("filterNotifier");
@@ -30,10 +32,7 @@ let blockedPerPage = new ext.PageMap();
  * @param  {Page} page
  * @return {Number}
  */
-exports.getBlockedPerPage = function(page)
-{
-  return blockedPerPage.get(page) || 0;
-};
+exports.getBlockedPerPage = page => blockedPerPage.get(page) || 0;
 
 FilterNotifier.on("filter.hitCount", (filter, newValue, oldValue, page) =>
 {
@@ -57,11 +56,10 @@ FilterNotifier.on("filter.hitCount", (filter, newValue, oldValue, page) =>
 
 Prefs.on("show_statsinicon", () =>
 {
-  ext.pages.query({}, function(pages)
+  ext.pages.query({}, pages =>
   {
-    for (var i = 0; i < pages.length; i++)
+    for (let page of pages)
     {
-      let page = pages[i];
       let badge = null;
 
       if (Prefs.show_statsinicon)