The problem is when create/rename/drop users, the statement was logged regardless of error, even if no data has been changed, the statement was logged.

After this patch, create/rename/drop users don't write the binlog if the statement makes no changes, if the statement does make any changes, log the statement with possible error code.

This patch is based on the patch for BUG#29749, which is not pushed


sql/sql_acl.cc:
  when create/rename/drop users, don't write the binlog if the statement make no changes
mysql-test/r/rpl_user.result:
  New BitKeeper file ``mysql-test/r/rpl_user.result''
mysql-test/t/rpl_user.test:
  New BitKeeper file ``mysql-test/t/rpl_user.test''