[gnome-shell] Fix typo in gnome-shell-extension-prefs

[Stefano Facchini <sfacchini src gnome org>]

commit 9bcce4f2713ae6bad2d7c1020f1ea42d588a20c7
Author: Stefano Facchini <stefano facchini gmail com>
Date:   Fri Feb 1 19:33:20 2013 +0100

    Fix typo in gnome-shell-extension-prefs
    
    Environment variables should be checked for zero length,
    instead of non-zero. This prevented the script to run
    correctly in a jhbuild shell for example.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=693031

 src/gnome-shell-extension-prefs.in |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/gnome-shell-extension-prefs.in b/src/gnome-shell-extension-prefs.in
index acc2cb1..a1690a6 100644
--- a/src/gnome-shell-extension-prefs.in
+++ b/src/gnome-shell-extension-prefs.in
@@ -1,12 +1,12 @@
 #!/bin/sh
 
-if [ -n "$GI_TYPELIB_PATH" ]; then
+if [ -z "$GI_TYPELIB_PATH" ]; then
     export GI_TYPELIB_PATH= pkglibdir@
 else
     export GI_TYPELIB_PATH= pkglibdir@:$GI_TYPELIB_PATH
 fi
 
-if [ -n "$LD_LIBRARY_PATH" ] ; then
+if [ -z "$LD_LIBRARY_PATH" ] ; then
     export LD_LIBRARY_PATH= pkglibdir@
 else
     export LD_LIBRARY_PATH= pkglibdir@:$LD_LIBRARY_PATH