** revision-id: vasil.dimov@oracle.com-20140403163612-rjymqwuzkh6vs6dj
  ** committer: Vasil Dimov <vasil.dimov@oracle.com>
  ** branch nick: mysql-trunk
  ** timestamp: Thu 2014-04-03 19:36:12 +0300
  ** message:
  **   Followup to vasil.dimov@oracle.com-20140403070651-w1nefsafrqeid6ct:
  **   Increase the margin of allowed deviance for n_rows - with 4k page size
  **   it could sometimes be 745 (27% away from the actual value 1024).