[libhandy] example: Bind showing decorations on all headerbars to the fold

[Alexander Mikhaylenko <alexm src gnome org>]

commit e0b14437946ed9cb5b5c776302bdb5f5c8fabbd5
Author: Adrien Plazas <kekun plazas laposte net>
Date:   Wed Jun 24 10:15:44 2020 +0200

    example: Bind showing decorations on all headerbars to the fold

 examples/hdy-demo-window.ui | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/examples/hdy-demo-window.ui b/examples/hdy-demo-window.ui
index 2307b9b7..a3894a60 100644
--- a/examples/hdy-demo-window.ui
+++ b/examples/hdy-demo-window.ui
@@ -2273,6 +2273,7 @@
     </widgets>
   </object>
   <object class="HdyHeaderGroup" id="header_group">
+    <property name="decorate-all" bind-source="content_box" bind-property="folded" bind-flags="sync-create"/>
     <headerbars>
       <headerbar name="header_bar"/>
       <headerbar name="default_header_bar"/>