(CHARSET_BYTE_SIZE): Moved to char-ucs.h.

(CHARSET_BYTE_SIZE): Moved to char-ucs.h.
(XCHARSET_BYTE_SIZE): Likewise.

(decoding_table_remove_char): Moved to char-ucs.h.
(decoding_table_put_char): Likewise.

(put_char_ccs_code_point): Delete unused codes.

(put_char_ccs_code_point): Don't prepare a vector for decoding-table.

(put_char_ccs_code_point): Modify for `decoding_table_remove_char' and
`decoding_table_put_char'.
(remove_char_ccs): Modify for `decoding_table_remove_char'.

(remove_char_ccs): Store Qunbound instead of Qnil into encoding_table.
(make_charset): Use Qunbound instead Qnil as initial value of
decoding_table.

(decode_defined_char): New function; search mother.
(decode_builtin_char): Don't search mother if
XCHARSET_MAX_CODE(charset) == 0.
(charset_code_point): Search mother if XCHARSET_MAX_CODE(charset) == 0
even if code >= XCHARSET_MAX_CODE(charset).
(Fdecode_char): Use `decode_defined_char' instead of
`DECODE_DEFINED_CHAR'.
(complex_vars_of_mule_charset): Specify `Vcharset_ucs' as the
mother of `Vcharset_ucs_jis'.