chromium/third_party/blink/web_tests/external/wpt/html/browsers/history/joint-session-history/joint-session-history-remove-iframe.html

<!doctype html>
<meta charset="utf-8">
<title>Joint session history length does not include entries from a removed iframe.</title>
<meta name="timeout" content="long">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<body>
<iframe id="frame" src="about:blank"></iframe>
<script>
async_test(function(t) {
    t.step_timeout(() => {
        var child = document.getElementById("frame");
        var old_history_len = history.length;
        child.onload = () => {
            assert_equals(old_history_len + 1, history.length);
            document.body.removeChild(document.getElementById("frame"));
            assert_equals(old_history_len, history.length);
            t.done();
        }
        child.src = "joint-session-history-filler.html";
    }, 1000);
});
</script>
</body>