[gnome-control-center] printers: Destroy ppd selection dialog explicitly

[Felipe Borges <felipeborges src gnome org>]

commit 9f0733182afae1d8832168e3164777d06b226271
Author: Marek Kasik <mkasik redhat com>
Date:   Fri Feb 25 15:16:10 2022 +0100

    printers: Destroy ppd selection dialog explicitly
    
    Destroy PpPPDSelectionDialog in dispose method of PpNewPrinterDialog
    as its transient-for property was unset by previous commit
    and the dialog is not destroyed automatically now.

 panels/printers/pp-new-printer-dialog.c | 6 ++++++
 1 file changed, 6 insertions(+)
---
diff --git a/panels/printers/pp-new-printer-dialog.c b/panels/printers/pp-new-printer-dialog.c
index ea425d8b4..a3c0e487c 100644
--- a/panels/printers/pp-new-printer-dialog.c
+++ b/panels/printers/pp-new-printer-dialog.c
@@ -1824,6 +1824,12 @@ pp_new_printer_dialog_dispose (GObject *object)
   g_clear_object (&self->remote_cups_host);
   g_clear_object (&self->samba_host);
 
+  if (self->ppd_selection_dialog != NULL)
+    {
+      gtk_window_destroy (GTK_WINDOW (self->ppd_selection_dialog));
+      self->ppd_selection_dialog = NULL;
+    }
+
   if (self->num_of_dests > 0)
     {
       cupsFreeDests (self->num_of_dests, self->dests);