title: How do I make part of a TreeViewer cell bold?
body: <p>I currently want to write an Eclipse editor based on a JFace <code>TreeViewer</code>. I added a <code>CellLabelProvider</code> to the <code>TreeViewer</code>. If I set the font of a cell with directly in the <code>update</code> method of the <code>CellLabelProvider</code> to a bold font the label is shown bold. </p>
  
  <p>But I want only part of the label to be shown as bold. So I apply <code>StyleRange</code>s to the cell. Selected colors in the 'StyleRange's work perfectly, but setting the font of a <code>StyleRange</code> to a bold one, does not seem to work.</p>
  
  <p>Why is that and how do I fix it?</p>