added missing consts and pass objects by const reference instead of by value (patch 1205869)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@35665 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/ipcbase.h

@@ -48,7 +48,7 @@ class WXDLLIMPEXP_BASE wxConnectionBase: public wxObject
 public:
   wxConnectionBase(wxChar *buffer, int size); // use external buffer
   wxConnectionBase(); // use internal, adaptive buffer
-  wxConnectionBase(wxConnectionBase& copy);
+  wxConnectionBase(const wxConnectionBase& copy);
   ~wxConnectionBase(void);
 
   void SetConnected( bool c ) { m_connected = c; }