[gnome-control-center] build: Bump required GTK+ version

[Debarshi Ray <debarshir src gnome org>]

commit 4e45c08dc706e3791d64a5503c4b888305497c76
Author: Debarshi Ray <debarshir gnome org>
Date:   Wed Aug 21 18:38:53 2013 +0200

    build: Bump required GTK+ version
    
    It's required for gtk_button_new_from_icon_name.

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 12558f3..783ced5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -84,7 +84,7 @@ dnl Check that we meet the  dependencies
 dnl ==============================================
 
 GLIB_REQUIRED_VERSION=2.35.1
-GTK_REQUIRED_VERSION=3.9.11
+GTK_REQUIRED_VERSION=3.9.12
 PA_REQUIRED_VERSION=2.0
 CANBERRA_REQUIRED_VERSION=0.13
 GDKPIXBUF_REQUIRED_VERSION=2.23.0