[gtk/font-settings-fallback] wayland: Improve font setting fallback more

[Matthias Clasen <matthiasc src gnome org>]

commit dfea8c31d97379ff62635474ffde0d388b4b85ac
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Apr 7 14:28:39 2021 -0400

    wayland: Improve font setting fallback more
    
    We may get a response from the portal that contains
    no useful settings at all. In that case, we should
    fallback as well.
    
    Fixes: #3838

 gdk/wayland/gdkscreen-wayland.c | 8 ++++++++
 1 file changed, 8 insertions(+)
---
diff --git a/gdk/wayland/gdkscreen-wayland.c b/gdk/wayland/gdkscreen-wayland.c
index e9a4f0e4c2..6f8b5e8d93 100644
--- a/gdk/wayland/gdkscreen-wayland.c
+++ b/gdk/wayland/gdkscreen-wayland.c
@@ -745,6 +745,14 @@ init_settings (GdkScreen *screen)
           goto fallback;
         }
 
+      if (g_variant_n_children (ret) == 0)
+        {
+          g_debug ("Received no portal settings");
+          g_clear_pointer (&ret, g_variant_unref);
+
+          goto fallback;
+        }
+
       g_variant_get (ret, "(a{sa{sv}})", &iter);
 
       while (g_variant_iter_loop (iter, "{s@a{sv}}", &schema, &val))