<!DOCTYPE HTML>
<head>
    <style>
        body {
            overflow: hidden;
            margin: 0;
        }

        .svgcanvas {
            position: relative;
            width: 3800px;
            height: 600px;
            display: inline-block;
            overflow: hidden;
        }
        
        .indicator {
            position: absolute;
            top: 0;
            left: 0;
            width: 3800px; /* Trigger composited tiling */
            height: 600px;
            display: inline-block;
            background-color: red;
        }
        
        .composited {
            -webkit-transform: translateZ(0);
        }
        
        #svgroot {
            position: absolute;
            top: 0;
            left: 0;
            background-color: gray;
        }
        
        svg {
            border: 4px solid black;
            box-sizing: border-box;
        }
    </style>
    <script>
        if (window.testRunner)
            testRunner.waitUntilDone();

        function doTest()
        {
            window.setTimeout(function() {
                var svg = document.getElementById('svgroot');
                svg.setAttribute('x', 640);
                svg.setAttribute('y', 480);
                svg.setAttribute('width', 1920);
                svg.setAttribute('height', 1400);
                var background = document.getElementById('canvasBackground');
                background.setAttribute('x', 540);
                background.setAttribute('y', 480);

                if (window.testRunner)
                    testRunner.notifyDone();
            }, 0);
        }
        window.addEventListener('load', doTest, false);
    </script>
</head>
    <!-- You should see no red -->
    <div class="indicator"></div>
    <div class="composited svgcanvas">
        <svg id="svgroot" width="640" height="480" overflow="visible">
          <svg id="canvasBackground" width="640" height="480" overflow="none">
            <rect width="100%" height="100%" fill="green"/>
          </svg>
        </svg>
    </div>
</div>