chromium/third_party/blink/web_tests/external/wpt/focus/support/iframe-focuses-parent-same-site-inner.html

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>iframe focuses parent same site inner</title>
</head>
<body>
<script>
window.onmessage = function() {
    parent.focus();
    setTimeout(function() {
        parent.postMessage("finished", "*");
    }, 500);
}
</script>
</body>
</html>