title: PopUp menu will not center horizontal
body: <p>I instantiate a popup menu in Xamarin studio / C# in this way:</p>
  
  <pre><code>PopupMenu puMenu = new PopupMenu(myActivity, view, GravityFlags.CenterHorizontal);
  </code></pre>
  
  <p>With this I expect the puMenu to center horizontal, but this is not the case. The puMenu continues to be left aligned.</p>
  
  <p>If i replace "CenterHorzontal" with "Right" like this:</p>
  
  <pre><code>PopupMenu puMenu = new PopupMenu(myActivity, view, GravityFlags.Right);
  </code></pre>
  
  <p>the puMenu is right aligned as I expect.</p>
  
  <p>Any clues to whats wrong with the first statement?</p>