[gnome-mahjongg/arnaudb/modernize-code: 21/22] Replace deprecated method.

[Arnaud B. <arnaudb src gnome org>]

commit 3e55c868690b7037ee2e4f98ad7ef5ff6a53ac23
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Fri Mar 27 19:46:55 2020 +0100

    Replace deprecated method.

 src/gnome-mahjongg.vala | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/gnome-mahjongg.vala b/src/gnome-mahjongg.vala
index 1c1cbf7..5d15e56 100644
--- a/src/gnome-mahjongg.vala
+++ b/src/gnome-mahjongg.vala
@@ -724,7 +724,7 @@ public class Mahjongg : Gtk.Application
     {
         try
         {
-            Gtk.show_uri (window.get_screen (), "help:gnome-mahjongg", Gtk.get_current_event_time ());
+            Gtk.show_uri_on_window (window, "help:gnome-mahjongg", Gtk.get_current_event_time ());
         }
         catch (Error e)
         {