LayoutTests/fast/ruby/ruby-with-unbreakable-characters-incorrect-width-expected.html

<meta charset="UTF-8">
<style>
div {
  font-family: Ahem;
  font-size: 20px;
  width: 200px;
  border: 1px solid green;
  text-align-last: justify;
  height: 30px;
  overflow: hidden;
}
</style>
<div><ruby>XX<rt>XXXXXX</rt></ruby> <ruby>X<rt>XXX</rt><ruby>X<rt>XXX</rt></ruby></div>