<!DOCTYPE html>

<script src="../../resources/js-test-pre.js"></script>

<div id="a">
    <div id="b">
    </div>
</div>

<div id="c">
</div>

<script>
if (window.testRunner) {
    testRunner.dumpAsText();
    testRunner.dumpChildFramesAsText();
    testRunner.waitUntilDone();
}

var frame = document.createElement('iframe');
var a = document.getElementById('a');
var b = document.getElementById('b');
var c = document.getElementById('c');

onload = function() {
    b.appendChild(frame);

    frame.onload = function() {
        frame.contentDocument.body.innerHTML = 'Should be visible.';
    };

    frame.contentWindow.onunload = function() {
        b.parentNode.removeChild(b);
        shouldBeNull('frame.contentDocument');
        c.appendChild(b);
        shouldNotBe('frame.contentDocument', 'null');
        isSuccessfullyParsed();
        if (window.testRunner)
            testRunner.notifyDone();
    };

    a.parentNode.removeChild(a);
};
</script>