chromium/third_party/blink/web_tests/fast/borders/borderRadiusInvalidColor.html

<style>
.myDiv {
    -webkit-border-radius : 5px;
    width: 50px;
    color: red;
    background-color: lightblue;
    border: 3px solid;
}
</style>
This tests that border radius will choose the foreground color when no border color is specified.

<div class="myDiv">test</div>