tdf#119690 on 'apply' options dialog is still up, use that as parent

Change-Id: Icecf6bd2981a5b96c594a706238e8baf9b5a8149
Reviewed-on: https://gerrit.libreoffice.org/59980
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

cui/source/options/treeopt.cxx

@@ -699,7 +699,7 @@ IMPL_LINK_NOARG(OfaTreeOptionsDialog, ApplyHdl_Impl, Button*, void)
     {
         SolarMutexGuard aGuard;
         ::svtools::executeRestartDialog(comphelper::getProcessComponentContext(),
-                                        m_pParent->GetFrameWeld(), eRestartReason);
+                                        GetFrameWeld(), eRestartReason);
     }
 }