Ajax: notify channel is not used

src/jio.js

@@ -66,7 +66,7 @@
    */
   function ajax(param) {
     var xhr = new XMLHttpRequest();
-    return new RSVP.Promise(function (resolve, reject, notify) {
+    return new RSVP.Promise(function (resolve, reject) {
       var k;
       xhr.open(param.type || "GET", param.url, true);
       xhr.responseType = param.dataType || "";
@@ -84,7 +84,6 @@
         resolve(e);
       });
       xhr.addEventListener("error", reject);
-      xhr.addEventListener("progress", notify);
       if (typeof param.xhrFields === 'object' && param.xhrFields !== null) {
         for (k in param.xhrFields) {
           if (param.xhrFields.hasOwnProperty(k)) {