[mutter] clutter/fixed-layout: Ignore hidden children in size request

[Marge Bot <marge-bot src gnome org>]

commit d2c46162427ebaa8ba244643e29d9f3a1082538b
Author: Florian Müllner <fmuellner gnome org>
Date:   Wed Jun 29 15:17:05 2022 +0200

    clutter/fixed-layout: Ignore hidden children in size request
    
    Hidden actors aren't only invisible, they should also not take
    up any size.
    
    Found in the context of
    https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2347
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2488>

 clutter/clutter/clutter-fixed-layout.c | 6 ++++++
 1 file changed, 6 insertions(+)
---
diff --git a/clutter/clutter/clutter-fixed-layout.c b/clutter/clutter/clutter-fixed-layout.c
index 095f2d7524..9f68bb1757 100644
--- a/clutter/clutter/clutter-fixed-layout.c
+++ b/clutter/clutter/clutter-fixed-layout.c
@@ -66,6 +66,9 @@ clutter_fixed_layout_get_preferred_width (ClutterLayoutManager *manager,
     {
       gfloat child_x, child_min, child_natural;
 
+      if (!clutter_actor_is_visible (child))
+        continue;
+
       child_x = clutter_actor_get_x (child);
 
       clutter_actor_get_preferred_size (child,
@@ -108,6 +111,9 @@ clutter_fixed_layout_get_preferred_height (ClutterLayoutManager *manager,
     {
       gfloat child_y, child_min, child_natural;
 
+      if (!clutter_actor_is_visible (child))
+        continue;
+
       child_y = clutter_actor_get_y (child);
 
       clutter_actor_get_preferred_size (child,