chromium/third_party/blink/web_tests/fast/css/cssom-modify-font-face-rule.html

<!DOCTYPE html>
<html>
<head>
<script>
function runTest() {
    document.body.offsetLeft;
    document.styleSheets[0].cssRules[0].style.fontFamily = "f2";
}
</script>
</head>
<body onload="runTest()">
<style id="target">
@font-face {
    font-family: f1;
    font-weight: 100;
    src: url(../../resources/Ahem.ttf);
}
</style>
<!-- crbug.com/305885: when removing stylesheets, consider @font-face rules. -->
<span style="font-family: f1; font-weight: 100">A</span>
</body>
</html>