[gtk] Enable variations and features for font explorer

[Matthias Clasen <matthiasc src gnome org>]

commit 6b3091856b933147575ad46c9ab9b1e5cee4567f
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Mar 31 21:31:11 2018 -0400

    Enable variations and features for font explorer

 demos/gtk-demo/font-features.ui | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/demos/gtk-demo/font-features.ui b/demos/gtk-demo/font-features.ui
index 2cc89c92bc..7d10947a24 100644
--- a/demos/gtk-demo/font-features.ui
+++ b/demos/gtk-demo/font-features.ui
@@ -42,6 +42,7 @@
                         <property name="can-focus">1</property>
                         <property name="receives-default">1</property>
                         <property name="font">Sans 12</property>
+                        <property name="level">family|style|size|variations|features</property>
                         <signal name="font-set" handler="font_changed" swapped="no"/>
                       </object>
                     </child>