<!DOCTYPE html> <!-- webkit-test-runner [ AsyncOverflowScrollingEnabled=true ] -->
<html>
<head>
    <style>
        .scroller {
            width: 400px;
            height: 450px;
            border: 2px solid black;
            overflow: scroll;
        }
        
        .contents {
            height: 300%;
        }
    </style>
    <script>
        if (window.internals)
            internals.setUsesOverlayScrollbars(true);
    
        window.addEventListener('load', () => {
            // Trigger scrollbar display.
            let scroller = document.querySelector('.scroller');
            scroller.scrollTop = 10;
        }, false);
    </script>
</head>
<body>
    <div class="scroller">
        <div class="contents">
        </div>
    </div>
</body>
</html>