title: InvalidStateError - Kendo UI Upload
body: <p>I keep getting this weird bug where when I try to set my Authorization header, I keep getting 'InvalidStateError'. Here is my code:</p>
  
  <pre><code>$("#files").kendoUpload({
                          async: {
                              saveUrl: myApiUrl + "/" + id,
                              autoUpload: true
                          },
                          upload: function(e) {
                              var xhr = e.XMLHttpRequest;
                              if (xhr) {
                                  xhr.addEventListener("readystatechange", function onReady(e) {
                                      if (xhr.readyState === 1 /* OPENED */) {
                                              xhr.setRequestHeader("Authorization", "Bearer " + accessToken);
                                      }
                                  });
                              }
                          }
                      });
  </code></pre>