Windows with custom surface are not visible with gtk 3.24.17

7f12dc2b broke applications with wlr-layer-shell toplevels. Initially reported at github:Alexays/Waybar#642, /r/swaywm/comments/fugubl/gtk3_update_killed_waybar/

Custom surfaces such as wlr-layer-shell aren't going to call xdg_surface_configure, thus needs_initial_configure helper added in !1620 (merged) should also check for impl->use_custom_surface.