XHR test on data uris

HTML

<body>
    <pre id='log'></pre>
</body>

JavaScript

function log(msg) {
    $('log').appendChild(document.createTextNode(msg + '\n'));
}

function onXhrChange() {
    log('XHR ready state: ' + this.readyState);
    if (this.readyState == 4) 
        log('Response: ' + this.responseText);
}

var req = new XMLHttpRequest();
req.onreadystatechange = onXhrChange;
req.open('GET', 'data urida');
try {
  req.send();
} catch(err) {
    log('send failed: ' + err.message);
}