url: use primordials for safe method

Author: Connormiha

lib/url.js

@@ -22,6 +22,8 @@
 'use strict';
 
 const {
+  ArrayPrototypeAt,
+  ArrayPrototypeJoin,
   Boolean,
   Int8Array,
   ObjectAssign,
@@ -919,7 +921,7 @@ Url.prototype.resolveObject = function resolveObject(relative) {
   // If a url ENDs in . or .., then it must get a trailing slash.
   // however, if it ends in anything else non-slashy,
   // then it must NOT get a trailing slash.
-  let last = srcPath.at(-1);
+  let last = ArrayPrototypeAt(srcPath, -1);
   const hasTrailingSlash = (
     ((result.host || relative.host || srcPath.length > 1) &&
     (last === '.' || last === '..')) || last === '');
@@ -952,7 +954,7 @@ Url.prototype.resolveObject = function resolveObject(relative) {
     srcPath.unshift('');
   }
 
-  if (hasTrailingSlash && (srcPath.join('/').at(-1) !== '/')) {
+  if (hasTrailingSlash && ArrayPrototypeAt(ArrayPrototypeJoin(srcPath,'/'), -1) !== '/')) {
     srcPath.push('');
   }