move variable definitions to more appropriate places, remove now-empty src/common/datacmn.cpp

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66592 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/msgout.cpp

@@ -195,6 +195,8 @@ void wxMessageOutputLog::Output(const wxString& str)
 
 #if wxUSE_GUI && wxUSE_MSGDLG
 
+extern WXDLLEXPORT_DATA(const char) wxMessageBoxCaptionStr[] = "Message";
+
 void wxMessageOutputMessageBox::Output(const wxString& str)
 {
     wxString out(str);