From 0435d1cf2a488f7d3f15ccdceaeb763f90fcce8c Mon Sep 17 00:00:00 2001
From: Ryan Liu <asdfryan123@gmail.com>
Date: Tue, 5 Mar 2013 14:39:44 -0500
Subject: [PATCH] issue 83 IE9/10: returned if this.xhr was undefined

---
 lib/transports/polling-xhr.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/transports/polling-xhr.js b/lib/transports/polling-xhr.js
index deaf1615..27188c14 100644
--- a/lib/transports/polling-xhr.js
+++ b/lib/transports/polling-xhr.js
@@ -248,6 +248,9 @@ Request.prototype.onError = function(err){
  */
 
 Request.prototype.cleanup = function(){
+  if ('undefined' == typeof this.xhr ) {
+    return;
+  }
   // xmlhttprequest
   this.xhr.onreadystatechange = empty;