The protocol hooks do contain the thread priority hooks for RTCORBA. They
shouldn't be there, we need a new hook just for thread priority and these are
then only used by the RTCorba and RTPortableServer libraries so they don't need
to be in the core TAO lib. The methods are:

  int get_thread_CORBA_priority (CORBA::Short &);

  int get_thread_native_priority (CORBA::Short &);

  int get_thread_CORBA_and_native_priority (CORBA::Short &,
                                            CORBA::Short &);

  int set_thread_CORBA_priority (CORBA::Short);

  int set_thread_native_priority (CORBA::Short);