[gtk/gtk3-a11y-leak: 1/2] a11y: Fix ref counting in tree views

[Matthias Clasen <matthiasc src gnome org>]

commit d4f62b44d47e3dddfb57add4f1f76cab0297584d
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Jun 11 08:53:46 2021 -0400

    a11y: Fix ref counting in tree views
    
    GtkContainerCellAccessible wasn't unsetting accessible
    parents. Fix that.
    
    By itself, this doesn't help for freeing a memory leak,
    since AtkObject keeps a ref on its parent, so we never
    free the GtkContainerCellAccessible as long as it has children.

 gtk/a11y/gtkcontainercellaccessible.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)
---
diff --git a/gtk/a11y/gtkcontainercellaccessible.c b/gtk/a11y/gtkcontainercellaccessible.c
index a756e3cadf..a40446fb47 100644
--- a/gtk/a11y/gtkcontainercellaccessible.c
+++ b/gtk/a11y/gtkcontainercellaccessible.c
@@ -30,12 +30,19 @@ struct _GtkContainerCellAccessiblePrivate
 G_DEFINE_TYPE_WITH_PRIVATE (GtkContainerCellAccessible, gtk_container_cell_accessible, 
GTK_TYPE_CELL_ACCESSIBLE)
 
 
+static void
+unset_child (gpointer child)
+{
+  atk_object_set_parent (ATK_OBJECT (child), NULL);
+  g_object_unref (child);
+}
+
 static void
 gtk_container_cell_accessible_finalize (GObject *obj)
 {
   GtkContainerCellAccessible *container = GTK_CONTAINER_CELL_ACCESSIBLE (obj);
 
-  g_list_free_full (container->priv->children, g_object_unref);
+  g_list_free_full (container->priv->children, unset_child);
 
   G_OBJECT_CLASS (gtk_container_cell_accessible_parent_class)->finalize (obj);
 }
@@ -157,6 +164,7 @@ gtk_container_cell_accessible_remove_child (GtkContainerCellAccessible *containe
   g_return_if_fail (GTK_IS_CELL_ACCESSIBLE (child));
   g_return_if_fail (container->priv->n_children > 0);
 
+  atk_object_set_parent (ATK_OBJECT (child), NULL);
   container->priv->children = g_list_remove (container->priv->children, child);
   container->priv->n_children--;