<!DOCTYPE html>

<html>
<head>
    <style>
        #slider {
            position: fixed;
            top: 100px;
            left: -100px;
            width: 200px;
            height: 100px;
            background-color: blue;
            border: 10px solid gray;
        }
        #slider.out {
            -webkit-transform: translateX(100px);
        }
    </style>
    <script>
        if (window.testRunner) {
            testRunner.dumpAsText();
            testRunner.waitUntilDone();
            if (window.internals)
                internals.settings.setAcceleratedCompositingForFixedPositionEnabled(true);
        }
        window.addEventListener('load', function() {
            window.setTimeout(function() {
                document.getElementById('slider').classList.add('out');
                if (window.testRunner) {
                    document.getElementById('layertree').innerText = window.internals.layerTreeAsText(document);
                    testRunner.notifyDone();
                }
            }, 0);
        }, false);
        
    </script>
</head>
<body>
<div id="slider"></div>
<pre id="layertree"></pre>
</body>
</html>