<html>
<head>
<style>

.flexbox {
    display: -webkit-flex;
}

.column {
    -webkit-flex-direction: column;
}
</style>
</head>
<body>
<div class="flexbox column" style="height:0px">
<div style="display:flex;background-color:red">This height should be 0. We are violating the spec (section 4.5) for now until we can implement nested column intrinsic sizing properly.</div>
</div>