Apply innodb-5.0-ss1696 snapshot

Fixes:
- Bug#20090: InnoDB: Error: trying to declare trx to enter InnoDB
- Bug#23710: crash_commit_before fails if innodb_file_per_table=1
  At InnoDB startup consider the case where log scan went beyond
  checkpoint_lsn as a crash and initiate crash recovery code path.
- Bug#28781: InnoDB increments auto-increment value incorrectly with ON DUPLICATE KEY UPDATE
  We need to do some special AUTOINC handling for the following case:
  INSERT INTO t (c1,c2) VALUES(x,y) ON DUPLICATE KEY UPDATE ...
  We need to use the AUTOINC counter that was actually used by
  MySQL in the UPDATE statement, which can be different from the
  value used in the INSERT statement.
- Bug#29097: fsp_get_available_space_in_free_extents() is capped at 4TB
  Fix by typecasting the variables before multiplying them, so that the
  result of the multiplication is of type "unsigned long long".
- Bug#29155: Innodb "Parallel recovery" is not prevented
  Fix by enabling file locking on FreeBSD.  It has been disabled because
  InnoDB has refused to start on FreeBSD & LinuxThreads, but now it
  starts just fine.