WebKit bug testcase: calc() is dropped from CSSOM

dabblet.css

/**
 * WebKit bug testcase: calc() is dropped from CSSOM
 */

dabblet.html

<script>
document.body.style.width = 'calc(100% - 10px)';
document.body.style.width = '-webkit-calc(100% - 10px)';
document.body.style.width = '-moz-calc(100% - 10px)';
document.write('"' + document.body.style.width + '"');
</script>

settings.json

{"view":"split-vertical","fontsize":"100","seethrough":"","prefixfree":"","page":"html"}