[gtk/ebassi/issue-4576] Update the accessible description of MenuButton

[Emmanuele Bassi <ebassi src gnome org>]

commit 37063e7a051521e732f1d1e44da19d31440cc172
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Sun Jan 2 00:35:53 2022 +0000

    Update the accessible description of MenuButton
    
    We update the labelled-by relation, but we never update the described-by
    one.
    
    Fixes: #4576

 gtk/gtkmenubutton.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/gtk/gtkmenubutton.c b/gtk/gtkmenubutton.c
index 67c3236508..fa695111b9 100644
--- a/gtk/gtkmenubutton.c
+++ b/gtk/gtkmenubutton.c
@@ -1028,6 +1028,7 @@ gtk_menu_button_set_icon_name (GtkMenuButton *menu_button,
    */
   gtk_accessible_update_relation (GTK_ACCESSIBLE (menu_button->button),
                                   GTK_ACCESSIBLE_RELATION_LABELLED_BY, menu_button, NULL,
+                                  GTK_ACCESSIBLE_RELATION_DESCRIBED_BY, menu_button, NULL,
                                   -1);
 
   image_widget = g_object_new (GTK_TYPE_IMAGE,
@@ -1164,6 +1165,7 @@ gtk_menu_button_set_label (GtkMenuButton *menu_button,
 
   gtk_accessible_update_relation (GTK_ACCESSIBLE (menu_button->button),
                                   GTK_ACCESSIBLE_RELATION_LABELLED_BY, menu_button->label_widget, NULL,
+                                  GTK_ACCESSIBLE_RELATION_DESCRIBED_BY, menu_button->label_widget, NULL,
                                   -1);
 
   menu_button->image_widget = NULL;