<script>
try {
    var req = new XMLHttpRequest;
    req.open("GET", "simple.txt", false);
    req.send(null);
    alert("FAIL, unexpected response: " + req.responseText);
} catch (ex) {
    // Loading should fail, because simple.txt is not in cache manifest.
    parent.postMessage("allDone", "*");
}
</script>