title: XHR get request URL in onreadystatechange
body: <p>Is there any way to get the URL of request in the "onreadystatechange" method?</p>
  
  <p>I want to run multiple XHR requests and know which of them comes back:</p>
  
  <pre><code>xhr.open("GET", "https://" + url[i], true);
  xhr.onreadystatechange = function(url) {
      console.log("Recieved data from " + url);
  };
  xhr.send();
  </code></pre>