(char_byte_table): New type.
(XCHAR_BYTE_TABLE): New macro.
(XSETCHAR_BYTE_TABLE): New macro.
(CHAR_BYTE_TABLE_P): New macro.
(GC_CHAR_BYTE_TABLE_P): New macro.
(struct Lisp_Char_Byte_Table): New structure.
(get_char_code_table): New interface.
(Emchar_to_byte_table): Deleted.
(get_byte_from_character_table): Deleted.
(struct Lisp_Charset): Add `encoding_table'; delete `to_byte1_table'
and `to_byte2_table'.
(CHARSET_ENCODING_TABLE): New macro.
(CHARSET_TO_BYTE1_TABLE): Deleted.
(CHARSET_TO_BYTE2_TABLE): Deleted.
(XCHARSET_ENCODING_TABLE): New macro.
(XCHARSET_TO_BYTE1_TABLE): Deleted.
(XCHARSET_TO_BYTE2_TABLE): Deleted.