Use event modifiers and accessors rather than m_ variables directly, which are now protected rather than public with 2.4 compatibility disabled

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@31454 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/lboxcmn.cpp

@@ -118,7 +118,7 @@ void wxListBoxBase::DeselectAll(int itemToLeaveSelected)
 
 void wxListBoxBase::Command(wxCommandEvent& event)
 {
-    SetSelection(event.m_commandInt, event.m_extraLong != 0);
+    SetSelection(event.GetInt(), event.GetExtraLong() != 0);
     (void)ProcessEvent(event);
 }