LayoutTests/css3/masking/clip-path-root-relative-bounds-expected.html

<style>
div {
    width: 500px;
    height: 200px;
    margin: 20px;
    background: blue;
    border: solid red 20px;
    -webkit-clip-path: circle(50% at 50% 50%) border-box;
}
</style>
<div></div>