[metacity/cowbell] don't draw rectangles with no size

[Thomas James Alexander Thurman <tthurman src gnome org>]

commit e1eec1b36df4d5cbcb992b45f4bdd5c6d10d11cf
Author: Thomas Thurman <tthurman gnome org>
Date:   Fri Oct 23 16:00:44 2009 -0400

    don't draw rectangles with no size

 src/ui/theme.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/ui/theme.c b/src/ui/theme.c
index 78a7cf8..4353778 100644
--- a/src/ui/theme.c
+++ b/src/ui/theme.c
@@ -346,7 +346,7 @@ draw_rectangle (ccss_stylesheet_t *stylesheet,
 					       (ccss_node_t*) &cowbell_nodes[style_id]);
   int horizontal_margin = 0;
 
-  if (!style) return;
+  if (!style || w==0 || h==0) return;
 
   if (honour_margins)
     {