Use ES5 syntax

cps/static/js/edit_books.js

@@ -8,18 +8,17 @@ tinymce.init({
         selector: "#description",
         branding: false,
         menubar: "edit view format",
-    language
+        language: language
     });
 
-
     if (!Modernizr.inputtypes.date) {
         $("#pubdate").datepicker({
             format: "yyyy-mm-dd",
-        language
+            language: language
         }).on("change", function () {
             // Show localized date over top of the standard YYYY-MM-DD date
-        let pubDate;
+            var pubDate;
-        const results = /(\d{4})[-\/\\](\d{1,2})[-\/\\](\d{1,2})/.exec(this.value); // YYYY-MM-DD
+            var results = /(\d{4})[-\/\\](\d{1,2})[-\/\\](\d{1,2})/.exec(this.value); // YYYY-MM-DD
             if (results) {
                 pubDate = new Date(results[1], parseInt(results[2], 10) - 1, results[3]) || new Date(this.value);
             }
@@ -29,6 +28,7 @@ if (!Modernizr.inputtypes.date) {
         }).trigger("change");
     }
 }
+
 /*
 Takes a prefix, query typeahead callback, Bloodhound typeahead adapter
  and returns the completions it gets from the bloodhound engine prefixed.
@@ -43,6 +43,7 @@ function prefixedSource(prefix, query, cb, bhAdapter) {
         cb(matches);
     });
 }
+
 function getPath() {
     var jsFileLocation = $("script[src*=edit_books]").attr("src");  // the js file path
     jsFileLocation = jsFileLocation.replace("/static/js/edit_books.js", "");   // the js folder path