[gnome-shell] build: Add dependency on Xtst

[Rico Tzschichholz <ricotz src gnome org>]

commit 3a14eb936317e3defed4c37444132de26d8837d0
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Thu Aug 8 10:20:05 2013 +0200

    build: Add dependency on Xtst
    
    Fix linker error caused by 137cbbd141ee9e6e8fa635d1800930e12578ed12

 configure.ac |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 48ab6ac..f0fe559 100644
--- a/configure.ac
+++ b/configure.ac
@@ -87,6 +87,7 @@ PKG_CHECK_MODULES(GNOME_SHELL, gio-unix-2.0 >= $GIO_MIN_VERSION
                               libgnome-menu-3.0 >= $GNOME_MENUS_REQUIRED_VERSION
                                $recorder_modules
                                gdk-x11-3.0 libsoup-2.4
+                               xtst
                               clutter-x11-1.0 >= $CLUTTER_MIN_VERSION
                               clutter-glx-1.0 >= $CLUTTER_MIN_VERSION
                                libstartup-notification-1.0 >= $STARTUP_NOTIFICATION_MIN_VERSION