<!DOCTYPE html> <!-- webkit-test-runner [ AsyncOverflowScrollingEnabled=true ] -->
<html>
<head>
    <style>
        #scroller {
            overflow: scroll;
            height: 400px;
            width: 400px;
            border: 1px solid black;
        }

        .composited {
            width: 200px;
            height: 200px;
            background-color: green;
            transform: translateZ(0);
        }

        .content {
            height: 700px;
        }
        
        .content.changed {
            height: 100px;
        }
    </style>
    <script>
        if (window.testRunner)
            testRunner.waitUntilDone();

        window.addEventListener('load', () => {
            scroller.scrollTo(0, 100);
            setTimeout(() => {
                document.querySelector('.content').classList.add('changed');
                if (window.testRunner)
                    testRunner.notifyDone();
            }, 0);
        }, false);
    </script>
</head>
<body>
    <section id="scroller">
        <div class="composited"></div>
        <div class="content"></div>
    </section>
</body>
</html>