[gtk/stackpage-fix-for-4-6] a11y: Realize GtkStackPage parent context before trying to get a ref

[Matthias Clasen <matthiasc src gnome org>]

commit 1860da7a1a57efc5e03f06c40dc99a0242f41748
Author: Sebastian Keller <skeller gnome org>
Date:   Wed May 25 14:56:05 2022 +0200

    a11y: Realize GtkStackPage parent context before trying to get a ref
    
    If a context is not realized, calling gtk_at_spi_context_to_ref() will
    return a null ref, because its path has not been initialized yet. This
    was already done for all other cases in get_parent_context_ref(), but
    was missing for the GtkStackPage case.
    
    Fixes: https://gitlab.gnome.org/GNOME/gtk/-/issues/4944

 gtk/a11y/gtkatspicontext.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)
---
diff --git a/gtk/a11y/gtkatspicontext.c b/gtk/a11y/gtkatspicontext.c
index 7c49929aff..a0086365c4 100644
--- a/gtk/a11y/gtkatspicontext.c
+++ b/gtk/a11y/gtkatspicontext.c
@@ -436,7 +436,11 @@ get_parent_context_ref (GtkAccessible *accessible)
         gtk_accessible_get_at_context (GTK_ACCESSIBLE (parent));
 
       if (parent_context != NULL)
-        res = gtk_at_spi_context_to_ref (GTK_AT_SPI_CONTEXT (parent_context));
+        {
+          gtk_at_context_realize (parent_context);
+
+          res = gtk_at_spi_context_to_ref (GTK_AT_SPI_CONTEXT (parent_context));
+        }
     }
 
   if (res == NULL)