[gtk+] Temporarily remove grid-span reftest

[Matthias Clasen <matthiasc src gnome org>]

commit 3605e6c900b14d283adcd38fc321133a8d078c27
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed May 1 16:55:12 2013 -0400

    Temporarily remove grid-span reftest
    
    This was testing grid size allocation changes that had to be
    reverted because they broke gnumeric.

 tests/reftests/grid-span.css    |   15 -----
 tests/reftests/grid-span.ref.ui |  134 ---------------------------------------
 tests/reftests/grid-span.ui     |   74 ---------------------
 3 files changed, 0 insertions(+), 223 deletions(-)