wayland: Emit GdkDisplay::setting-changed

We still generate the event too.
That will be removed in a future commit.

gdk/wayland/gdkscreen-wayland.c

@@ -123,6 +123,8 @@ notify_setting (GdkScreen   *screen,
   event.setting.action = GDK_SETTING_ACTION_CHANGED;
   event.setting.name = (gchar *)setting;
   gdk_event_put (&event);
+
+  gdk_display_setting_changed (gdk_screen_get_display (screen), setting);
 }
 
 typedef enum