[gtk/layout-manager-ref] widget: Don't lose a layout manager ref

[Matthias Clasen <matthiasc src gnome org>]

commit 9768f359316dc52a0898416f52e1fc09c6c40474
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Jul 3 13:16:35 2019 +0000

    widget: Don't lose a layout manager ref
    
    gtk_widget_set_layout_manager is transfer-full,
    so we must give it a new reference from set_property
    to implement object property semantics properly.

 gtk/gtkwidget.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index dd6e67dda7..42ba750375 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -2303,7 +2303,7 @@ gtk_widget_set_property (GObject         *object,
         gtk_css_node_set_name (priv->cssnode, GTK_WIDGET_GET_CLASS (widget)->priv->css_name);
       break;
     case PROP_LAYOUT_MANAGER:
-      gtk_widget_set_layout_manager (widget, g_value_get_object (value));
+      gtk_widget_set_layout_manager (widget, g_value_dup_object (value));
       break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);