<!DOCTYPE html> <!-- webkit-test-runner [ internal:AsyncOverflowScrollingEnabled=true ] -->
<html>
<head>
    <title>Tests repaints of shared backing when the sharing layers change</title>
    <style>
        .scrollable {
            overflow-y: scroll;
            height: 300px;
            width: 300px;
            margin: 10px;
            border: 1px solid black;
        }
		
		.box.sharing {
            background-color: blue;
		}
		
		.box {
			position: relative;
			top: 50px;
			left: 50px;
            width: 180px;
            height: 180px;
            background-color: green;
		}

        .spacer {
            height: 500px;
        }
    </style>
    <script>
        if (window.testRunner)
            testRunner.waitUntilDone();

        window.addEventListener('load', () => {
            let scroller = document.querySelector('.scrollable');
            requestAnimationFrame(() => {
                scroller.scrollTop = 250;
                requestAnimationFrame(() => {
                    scroller.scrollTop = 0;
                    if (window.testRunner)
                        testRunner.notifyDone();
                });
            });
        }, false);
    </script>
</head>
<body>
    <div class="scrollable">
        <div class="sharing box">
			<div class="inner box"></div>
        </div>
        <div class="spacer"></div>
    </div>
</body>
</html>