Refactor.

Refactor.

* gettext-tools/src/read-catalog-abstract.h (catalog_reader_seen_domain):
Renamed from po_callback_domain.
(catalog_reader_seen_message): Renamed from po_callback_message.
(catalog_reader_seen_comment): Renamed from po_callback_comment.
(catalog_reader_seen_comment_dot): Renamed from po_callback_comment_dot.
(catalog_reader_seen_comment_filepos): Renamed from po_callback_comment_filepos.
(catalog_reader_seen_comment_special): Renamed from po_callback_comment_special.
(catalog_reader_seen_generic_comment): Renamed from
po_callback_comment_dispatcher.
* gettext-tools/src/read-catalog-abstract.c (catalog_reader_seen_domain):
Renamed from po_callback_domain.
(catalog_reader_seen_message): Renamed from po_callback_message.
(catalog_reader_seen_comment): Renamed from po_callback_comment.
(catalog_reader_seen_comment_dot): Renamed from po_callback_comment_dot.
(catalog_reader_seen_comment_filepos): Renamed from po_callback_comment_filepos.
(catalog_reader_seen_comment_special): Renamed from po_callback_comment_special.
(parse_comment_filepos, parse_comment_solaris_filepos): Update.
(catalog_reader_seen_generic_comment): Renamed from
po_callback_comment_dispatcher. Update.
* gettext-tools/src/po-gram-gen.y: Update.
* gettext-tools/src/read-properties.c (properties_parse): Update.
* gettext-tools/src/read-stringtable.c (special_comment_finish,
comment_line_end, stringtable_parse): Update.