[gnome-shell] st/theme-node-transition: Guard against 0-sized offscreen box

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

commit 71d503dc6e5aa4a08bbd9df01b3034f0a5d5786c
Author: Florian Müllner <fmuellner gnome org>
Date:   Fri Jun 3 03:19:04 2022 +0200

    st/theme-node-transition: Guard against 0-sized offscreen box
    
    We know beforehand that setting up the framebuffers will fail in
    that case, so we can avoid cluttering the log with warnings.
    
    (Although the warning would likely indicate a stylesheet bug)
    
    https://gitlab.gnome.org/GNOME/gnome-shell-extensions/-/issues/289
    
    Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2326>

 src/st/st-theme-node-transition.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/src/st/st-theme-node-transition.c b/src/st/st-theme-node-transition.c
index 61199b437e..20b1476d2d 100644
--- a/src/st/st-theme-node-transition.c
+++ b/src/st/st-theme-node-transition.c
@@ -369,7 +369,8 @@ st_theme_node_transition_paint (StThemeNodeTransition *transition,
       priv->last_allocation = *allocation;
 
       calculate_offscreen_box (transition, allocation);
-      priv->needs_setup = !setup_framebuffers (transition, allocation,
+      priv->needs_setup = clutter_actor_box_get_area (&priv->offscreen_box) == 0 ||
+                          !setup_framebuffers (transition, allocation,
                                                resource_scale);
 
       if (priv->needs_setup) /* setting up framebuffers failed */