[gtk/wip/exalm/test: 13/37] tests: Fix testdnd popup

[Alexander Mikhaylenko <alexm src gnome org>]

commit f2542e95f9fcd1aaf617c0f53d50b8ffabcf96c8
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Mon May 11 03:38:10 2020 +0500

    tests: Fix testdnd popup
    
    Don't use GtkContainer API for GtkWindow.

 tests/testdnd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/tests/testdnd.c b/tests/testdnd.c
index f6659a54c4..b81f938dca 100644
--- a/tests/testdnd.c
+++ b/tests/testdnd.c
@@ -463,7 +463,7 @@ popup_cb (gpointer data)
                g_signal_connect (dest, "drop", G_CALLBACK (popup_drop), NULL);
                 gtk_widget_add_controller (button, GTK_EVENT_CONTROLLER (dest));
              }
-         gtk_container_add (GTK_CONTAINER (popup_window), grid);
+         gtk_window_set_child (GTK_WINDOW (popup_window), grid);
        }
       gtk_widget_show (popup_window);
       popped_up = TRUE;