<!DOCTYPE html>
<p>FAIL</p>
<iframe src="data:text/html,FAIL"></iframe>
<script type="text/x-isolate" id="s1">

window.onunload = function() {
    Window;
};

</script>
<script>

window.onload = function() {
    if (window.testRunner) {
        testRunner.waitUntilDone();
        testRunner.dumpAsText();

        var iframeElement = document.querySelector('iframe');
        iframeElement.focus();
        testRunner.evaluateScriptInIsolatedWorld(0, document.querySelector('#s1').textContent);

        iframeElement.onload = function() {
            document.body.textContent = 'PASS';
            testRunner.notifyDone();
        };
        iframeElement.src = 'data:text/html,PASS';
    }
};

</script>
</body>
</html>