gconf: improved to enable GTK+ support (for gconf-sanity-check) if possible

Note:

Initial reason for this change was that the gnome-session package was failing
because it couldn't find 'gconf-sanity-check'.

gnome2/gconf/gconf.conf

@@ -2,7 +2,7 @@
 # This copyright note is auto-generated by ./scripts/Create-CopyPatch.
 #
 # Filename: package/.../gconf/gconf.conf
-# Copyright (C) 2006 The OpenSDE Project
+# Copyright (C) 2006 - 2011 The OpenSDE Project
 # Copyright (C) 2004 - 2006 The T2 SDE Project
 # Copyright (C) 1998 - 2004 Clifford Wolf
 #
@@ -25,3 +25,9 @@ xdg_pc() {
 
 hook_add postmake 5 "xdg_pc"
 
+# GTK+ support (for gconf-sanity-check)
+if pkginstalled -f gtk+; then
+	var_append extraconfopt ' ' '--enable-gtk'
+	# which gtk+ version to compile against (2.0|3.0) (default: 3.0)
+	var_append extraconfopt ' ' "--with-gtk=$( pkgprefix ver gtk+ | cut -d '.' -f1 ).0"
+fi