<!DOCTYPE html> <!-- webkit-test-runner [ AsyncOverflowScrollingEnabled=true ] -->
<html>
<head>
    <title>Tests that the sharing layer still has backing store and paints shared layers after a tree config change</title>
    <style>
        .scrollable {
            overflow-y: scroll;
            height: 400px;
            width: 300px;
            margin: 10px;
            border: 1px solid black;
        }

        .sharing {
            margin: 20px;
            width: 150px;
            height: 130px;
            background-color: green;
            opacity: 0.75;
        }
    
        .spacer {
            height: 500px;
            width: 20px;
            background-color: silver;
        }
        
        .spacer.changed {
            height: 100px;
        }
    </style>
    <script>
        if (window.testRunner)
            testRunner.waitUntilDone();

        window.addEventListener('load', () => {
            setTimeout(() => {
                document.querySelector('.spacer').classList.add('changed');
                if (window.testRunner)
                    testRunner.notifyDone();
            }, 0);
        }, false);
    </script>
</head>
<body>
    <div class="scrollable">
        <div class="sharing">
        </div>
        <div class="spacer"></div>
    </div>
</body>
</html>