[racket] no check syntax arrows in 5.1.1

An hour and a half ago, Neil Van Dyke wrote:
> Someone, I forget who, mentioned that the Check Syntax arrows no longer 
> appear in 5.1.1 under Linux (at least not for me and the other person).  
> They *do* still work for me in 5.1, so this seems to be a regression in 
> 5.1.1.
> 
> I really like the arrows and miss them.  Can we get them back soon?

This is one part of the two problems that PR11778 converged to:

  http://bugs.racket-lang.org/query/?cmd=view&pr=11778

The arrows are there, they're just not displayed for some reason.  If
you force a redraw (eg, move to a different desktop and back), you'll
see the arrows.

-- 
          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!