<svg xmlns='http://www.w3.org/2000/svg'>
    <defs>
        <linearGradient id='test'>
            <stop id='stop' offset='0' stop-color='red' />
        </linearGradient>
    </defs>
    <rect fill="url(#test)" width='100' height='100' />
    <script>
    <![CDATA[
        if (window.layoutTestController)
            layoutTestController.waitUntilDone();
        var loaded = function() {
            var stop = document.getElementById("stop");
            stop.style.stopColor = 'green';
            if (window.layoutTestController)
                layoutTestController.notifyDone();
        }
        window.setTimeout(loaded, 0);
    ]]>
    </script>
</svg>