[gtk+] reftests: fix background-size reftest

[Cosimo Cecchi <cosimoc src gnome org>]

commit 868b28b5033f675f4993b33fa4e693632395b51b
Author: Cosimo Cecchi <cosimoc gnome org>
Date:   Mon Apr 30 12:54:45 2012 -0400

    reftests: fix background-size reftest
    
    We have to be careful and not set the background on the labels
    themselves.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=670743

 tests/reftests/background-size.css |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/tests/reftests/background-size.css b/tests/reftests/background-size.css
index 5dbff999..aae6f9f 100644
--- a/tests/reftests/background-size.css
+++ b/tests/reftests/background-size.css
@@ -1,6 +1,6 @@
 @import "reset-to-defaults.css";
 
-* {
+.button {
   background-image: url("border-image-balls.png");
   color: black;
   text-shadow: 1px 1px white;