[gnome-boxes] configure: Require gtk+ >= 3.22.20

[Debarshi Ray <debarshir src gnome org>]

commit 097af71ed041e3d679f0fb135dd2de8abca34344
Author: Debarshi Ray <debarshir gnome org>
Date:   Wed Sep 6 19:04:43 2017 +0200

    configure: Require gtk+ >= 3.22.20
    
    In a following patch, we will need to use GtkBuilder's "type-func"
    attribute to override its built-in heuristics. Prior to this,
    GtkBuilder wouldn't let the "type-func" override the heuristics if the
    "class" attribute was also present. On the other hand, older Vala
    compilers treat the "class" attribute as mandatory.
    
    It's slightly more convenient to bump the gtk+ requirement than Vala
    because gtk+-3.22.x is a long-term stable series, so older
    distributions are likely to keep it updated.
    
    See:
    https://bugzilla.gnome.org/show_bug.cgi?id=786932
    https://bugzilla.gnome.org/show_bug.cgi?id=787033
    https://bugs.webkit.org/show_bug.cgi?id=175937
    
    https://bugzilla.gnome.org/show_bug.cgi?id=786679

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 4024aa9..f67b5e7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -54,7 +54,7 @@ GLIB_MIN_VERSION=2.52.0
 AC_SUBST(GLIB_MIN_VERSION)
 GOBJECT_INTROSPECTION_MIN_VERSION=0.9.6
 GOVIRT_MIN_VERSION=0.3.4
-GTK_MIN_VERSION=3.19.8
+GTK_MIN_VERSION=3.22.20
 GTK_VNC_MIN_VERSION=0.4.4
 LIBVIRT_GLIB_MIN_VERSION=0.2.3
 LIBVIRT_GCONFIG_MIN_VERSION=0.2.0