LayoutTests/fast/inline/trailing-whitespace-content-with-overflowing-inline-box.html

<style>
div {
  font-family: Ahem;
  font-size: 15px;
  width: 40px;
  color: green;
}
span {
  padding-left: 25px;
  border-right: 15px solid green;
}
</style>
<!-- While the border-right makes the content overflow the line, it should stick with the X (and the collapsed whitespace) -->
<div><span>X </span>X</p>