in InnoDB tables.


mysql-test/r/innodb.result:
  New tests.
mysql-test/t/innodb.test:
  New tests.
sql/ha_innodb.cc:
  Add reset_auto_increment.
sql/ha_innodb.h:
  Add reset_auto_increment.
sql/handler.h:
  Add reset_auto_increment.
sql/sql_delete.cc:
  Call handler->reset_auto_increment when needed.