avoid setting initial position if it was not specified, broken in r70734

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74682 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/toplevel.cpp

@@ -664,7 +664,7 @@ bool wxTopLevelWindowGTK::Create( wxWindow *parent,
     PostCreation();
 
 #ifndef __WXGTK3__
-    if ((m_x != -1) || (m_y != -1))
+    if (pos != wxDefaultPosition)
         gtk_widget_set_uposition( m_widget, m_x, m_y );
 #endif