third_party/WebKit/LayoutTests/compositing/overflow/border-radius-on-grandparent-composited-grandchild.html

<style>
.outermost {
	border: 4px solid #000;
	width: 200px;
	height: 200px;
	border-radius: 40px;
	overflow: hidden;
}

.middle {
  border: 4px solid #888;
  background-color: #008;
  width: 200px;
  height: 200px;
  position: relative;
  left: 100px;
  top: 100px;
  overflow: hidden;
}

.inner {
  border: 4px solid #AAA;
	width: 80px;
	height: 400px;
	background-color: #080;
	position: relative;
  left: 20px;
  top: -100px;
  will-change: transform;
}
</style>

<div class="outermost">
	<div class="middle">
    <div class="inner">
    </div>
  </div>
</div>