fix toIsoString on date

Author: shdinx

core/lib_polyfill.ssjs

@@ -621,16 +621,15 @@ if (!Array.prototype.map) {
 ============================================================================ */ 
 
 if (!Date.prototype.toISOString) {
- (function() {
+ Date.prototype.toISOString = function() {
 
- function pad(number) {
- if (number < 10) {
- return '0' + number;
+ var pad = function(number) {
+ if (number < 10) {
+ return '0' + number;
+ }
+ return number;
  }
- return number;
- }
 
- Date.prototype.toISOString = function() {
  return this.getUTCFullYear() +
  '-' + pad(this.getUTCMonth() + 1) +
  '-' + pad(this.getUTCDate()) +
@@ -639,7 +638,5 @@ if (!Date.prototype.toISOString) {
  ':' + pad(this.getUTCSeconds()) +
  '.' + (this.getUTCMilliseconds() / 1000).toFixed(3).slice(2, 5) +
  'Z';
- };
-
- })();
+ }
 }