[gtk+] Broadway: Fix shm names

[Alexander Larsson <alexl src gnome org>]

commit c340dfeaf84685f655f6e5ea2ff02b9b48763c78
Author: Alexander Larsson <alexl redhat com>
Date:   Wed Apr 3 15:49:54 2013 +0200

    Broadway: Fix shm names
    
    We were sometimes getting zero chars in the name, making them
    shorter, due to an off-by-zero in the size.

 gdk/broadway/gdkbroadway-server.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gdk/broadway/gdkbroadway-server.c b/gdk/broadway/gdkbroadway-server.c
index cb9bdf4..adc28a0 100644
--- a/gdk/broadway/gdkbroadway-server.c
+++ b/gdk/broadway/gdkbroadway-server.c
@@ -506,7 +506,7 @@ make_valid_fs_char (char c)
 {
   char chars[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890";
 
-  return chars[c % sizeof (chars)];
+  return chars[c % (sizeof (chars) - 1)];
 }
 
 /* name must have at least space for 34 bytes */