Global linebreak_eawidth (linebreak_t *obj, unichar_t c): Use gcstring_columns() instead.
Global linebreak_lbclass (linebreak_t *obj, unichar_t c): Use gcstring_lbclass() or gcstring_lbclass_ext() instead.
Global linebreak_lbrule (propval_t b_idx, propval_t a_idx): Use linebreak_get_lbrule().
Global linebreak_set_user (linebreak_t *lbobj, linebreak_obs_prep_func_t user_func, void *user_data): Use linebreak_add_prep() instead.
Global linebreak_t::user_data: Use prep_data instead.
Global linebreak_t::user_func: Use prep_func instead.