<!DOCTYPE html>
<html>
<body>
<div id="tall" style="height: 1000em">
This page will force a layout on pagehide
</div>
</body>
<script>
window.addEventListener('pagehide', function(event) {
// Shrink the page.
document.getElementById('tall').style.height = '999em';
// Move the scroll position.
window.scroll(0, 100);
// Read the scroll position - this forces layout.
console.log(window.scrollY);
// Notify the opening window so tests can wait for this to run.
window.opener.postMessage('unloaded', '*');
});
// Notify the opening window that the page loaded, so tests can wait for it.
window.opener.postMessage('loaded', '*');
</script>
</html>