third_party/blink/web_tests/paint/invalidation/scroll/overflow-scroll-in-overflow-scroll-scrolled-expected.html - chromium/src - Git at Google

 <!DOCTYPE html>
 <script>
 onload = () => {
     outerDiv.scrollTop = 300;
     innerDiv.scrollTop = 400;
 }
 </script>
 <div style="height: 300px; overflow-y: scroll;" id="outerDiv">
     <div style="height: 300px;"></div>
     <div style="height: 400px; overflow-y: scroll;" id="innerDiv">
         <div style="height: 800px; width: 300px; background: green"></div>
     </div>
 </div>
	<!DOCTYPE html>
	<script>
	onload = () => {
	outerDiv.scrollTop = 300;
	innerDiv.scrollTop = 400;
	}
	</script>
	<div style="height: 300px; overflow-y: scroll;" id="outerDiv">
	<div style="height: 300px;"></div>
	<div style="height: 400px; overflow-y: scroll;" id="innerDiv">
	<div style="height: 800px; width: 300px; background: green"></div>
	</div>
	</div>