title: Mouse wheel not working when over ScrollViewer's child controls
body: <p>I was kind of expecting my ScrollViewer's child controls to hand the MouseWheel events back up the the ScrollViewer automatically, and that's not the case.</p>
  
  <p>I have a ScrollViewer with a ListBox in it.  If I manually resize the width of the ListBox to be less than the ScrollViewer, the MouseWheel works on all of the ScrollViewer but has no effect when the mouse is positioned above the ListBox.</p>
  
  <p>What's the standard way to do this?  Do I put an event trigger on the ListBox that fires the event on the parent?  Do I handle and reroute the event in the code behind?</p>