non-composited-scrolling-repaint-to-ancestor-backing.html

<!DOCTYPE html>
<style>
#container {
    overflow: scroll;
    width: 400px;
    height: 300px;
}

#clipping {
    overflow: hidden;
    height: 1000px;

    position: relative;
    z-index: 0;
}

#clipped {
    height: 10px;
    border: solid 1px black;
    transform: translateZ(0);
}
</style>
<div id="container">
    <div id="clipping">
        <div>Lorem ipsum</div>
        <div id="clipped"></div>
    </div>
</div>
<script src="../../resources/run-after-layout-and-paint.js"></script>
<script>
runAfterLayoutAndPaint(function() {
    document.getElementById('container').scrollTop = 1000;
}, true);
</script>

chromium/third_party/blink/web_tests/fast/scrolling/non-composited-scrolling-repaint-to-ancestor-backing.html