[gtk+] Work around a notebook tab rendering bug

[Matthias Clasen <matthiasc src gnome org>]

commit 8c3d77b4e8ee880c698755c2a36ec041199d3116
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Mar 20 11:19:06 2012 -0400

    Work around a notebook tab rendering bug
    
    This avoids assertions from gtk_render_frame_gap.

 tests/reftests/css-match-regions.css |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/tests/reftests/css-match-regions.css b/tests/reftests/css-match-regions.css
index 0b9807b..ecd127d 100644
--- a/tests/reftests/css-match-regions.css
+++ b/tests/reftests/css-match-regions.css
@@ -1,6 +1,7 @@
 @import "reset-to-defaults.css";
 
 * {
+  -GtkNotebook-tab-overlap: 0; /* work around a notebook tab rendering bug */
   color: blue;
 }