added wxDialog::GetParentForModalDialog() and use it to try to always create modal dialogs with a parent (slightly modified patch 1702962)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@45588 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/dirdlgg.cpp

@@ -78,6 +78,8 @@ bool wxGenericDirDialog::Create(wxWindow* parent,
 {
     wxBusyCursor cursor;
 
+    parent = GetParentForModalDialog(parent);
+
     if (!wxDirDialogBase::Create(parent, title, defaultPath, style, pos, sz, name))
         return false;