instead of SYS_TABLES.MIX_LEN, because the latter was not
initialized to zero in old MySQL 3.23 releases. This will break
existing MySQL/InnoDB 5.0.3-bk databases for which
SHOW TABLE STATUS displays Row_format=Compact.


innobase/dict/dict0crea.c:
  Write the "compact format" flag to N_COLS instead of MIX_LEN.
  Remove corruption analysis for MIX_LEN, as it has been tracked down
  to MySQL 3.23.4x not initializing MIX_LEN.
innobase/dict/dict0load.c:
  Read the "compact format" flag from N_COLS instead of MIX_LEN.