[gnome-session] build: Require glib 2.28.0

[Vincent Untz <vuntz src gnome org>]

commit cbe3d42b3595567ad60fdfbabbd37afcc74808aa
Author: Vincent Untz <vuntz gnome org>
Date:   Tue Mar 22 17:36:05 2011 +0100

    build: Require glib 2.28.0
    
    We use g_slist_free_full(), which appeared in 2.28.0.

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index d1891d2..d442eb6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -37,7 +37,7 @@ if test "x$enable_deprecation_flags" = "xyes"; then
    AC_SUBST([DISABLE_DEPRECATED_CFLAGS])
 fi
 
-GLIB_REQUIRED=2.16.0
+GLIB_REQUIRED=2.28.0
 GTK3_REQUIRED=2.90.7
 DBUS_GLIB_REQUIRED=0.76
 UPOWER_REQUIRED=0.9.0