[gtk/matthiasc/for-master: 7/8] Update action muxer hierarchy propertly

[Matthias Clasen <matthiasc src gnome org>]

commit 6652e146629efbd4b76fa01e374f0b21cf1d15fb
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Jun 1 13:49:26 2020 -0400

    Update action muxer hierarchy propertly
    
    When a new muxer appears, we must not only make it
    inherit from the parent, we also have to update all
    children to inherit from it.

 gtk/gtkwidget.c | 5 +++++
 1 file changed, 5 insertions(+)
---
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index 18a6b048fa..73f223ecd4 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -10718,6 +10718,7 @@ void
 _gtk_widget_update_parent_muxer (GtkWidget *widget)
 {
   GtkActionMuxer *muxer;
+  GtkWidget *child;
 
   muxer = (GtkActionMuxer*)g_object_get_qdata (G_OBJECT (widget), quark_action_muxer);
   if (muxer == NULL)
@@ -10725,6 +10726,10 @@ _gtk_widget_update_parent_muxer (GtkWidget *widget)
 
   gtk_action_muxer_set_parent (muxer,
                                gtk_widget_get_parent_muxer (widget, FALSE));
+  for (child = gtk_widget_get_first_child (widget);
+       child != NULL;
+       child = gtk_widget_get_next_sibling (child))
+    _gtk_widget_update_parent_muxer (child);
 }
 
 GtkActionMuxer *