[smuxi/experiments/gtk2_builder_pref_dialog] configure.ac: bump GTK# minimum version to 2.12.39

[Mirco M. M. Bauer <mmmbauer src gnome org>]

commit b4e088347b78950486e1fda3e1b60083875c84f0
Author: Mirco Bauer <meebey meebey net>
Date:   Sun Jun 5 12:25:15 2016 +0200

    configure.ac: bump GTK# minimum version to 2.12.39
    
    Since the use of Gtk.Builder we need GTK# >= 2.12.39 as that version added the
    needed auto binding of fields and signals from the UI.

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 10e3bda..9efdb9e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -609,7 +609,7 @@ AC_ARG_ENABLE([frontend-gnome],
 )
 if test "x$ENABLE_FRONTEND_GNOME" != "xno"; then
        PKG_CHECK_MODULES([GLIB_SHARP_20], [glib-sharp-2.0 >= 2.8])
-       PKG_CHECK_MODULES([GTK_SHARP_20], [gtk-sharp-2.0 >= 2.8])
+       PKG_CHECK_MODULES([GTK_SHARP_20], [gtk-sharp-2.0 >= 2.12.39])
        PKG_CHECK_MODULES([GLADE_SHARP_20], [glade-sharp-2.0 >= 2.8])
        
        AC_MSG_CHECKING([for gtk-sharp version >= 2.10])