<!DOCTYPE html>
<html>
<head>
    <style>
        .trigger {
            position: absolute;
            width: 20px;
            height: 20px;
            transform: translateZ(0);
            background-color: silver;
        }
        
        .composited-sharing {
            position: absolute;
            top: 15px;
            left: 15px;
            width: 800px;
            height: 200px;
            border: 1px solid blue;
        }

        .test {
            position: absolute;
            transform: scale(1, 1);
            top: 50px;
            left: 100px;
            background: orange;
            height: 100px;
            width: 100px;
        }
        
        body.changed .test {
            left: 200px;
        }

        body.changed.again .test {
            left: 400px;
        }
    </style>
    <script src="../../resources/ui-helper.js"></script>
    <script>
        if (window.testRunner) {
            testRunner.dumpAsText();
            testRunner.waitUntilDone();
        }

        window.addEventListener('load', () => {
            setTimeout(async () => {
                document.body.classList.add('changed');
                await UIHelper.renderingUpdate();
                
                if (window.internals)
                    window.internals.startTrackingRepaints();

                document.body.classList.add('again');

                if (window.internals)
                    document.getElementById('layers').textContent = window.internals.layerTreeAsText(document, internals.LAYER_TREE_INCLUDES_REPAINT_RECTS);

                if (window.testRunner)
                    testRunner.notifyDone();
            }, 0);
        }, false);
    </script>
</head>
<body>
    <div class="trigger"></div>
    <div class="composited-sharing">
        <div class="test"></div>
    </div>
<pre id="layers"></pre>
</body>
</html>