The code seemed to rely on Destroy() being called for deleting the dialog, but it's actually not used for child windows, so do it in dtor instead. Closes #15156. git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74030 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775