Problem: rpl_ndb_transaction fails because it assumes nothing
is written to the binlog at a certain point. However, ndb may
binlog updates in ndb system tables at a nondeterministic
time point after an ndb table update has been committed.
Fix: break the test into two. rpl_ndb_transaction still does
the ndb updates needed by the first half of the test. The new
test case rpl_bug26395 includes the part that assumes nothing
more will be written to the binlog.


mysql-test/include/sync_slave_io_with_master.inc:
  Like sync_slave_with_master, but only waits until the IO thread has
  synced; the SQL thread may still be behind.
mysql-test/suite/rpl/r/rpl_bug26395.result:
  New result file.
mysql-test/suite/rpl/t/rpl_bug26395-master.opt:
  New option file.
mysql-test/suite/rpl/t/rpl_bug26395-slave.opt:
  New option file.
mysql-test/suite/rpl/t/rpl_bug26395.test:
  - Moved second half of rpl_ndb_transaction here.
  - Improved the test case: instead of using a sleep,
  it waits for the slave's io thread to sync up to a proper
  position, and for the slave's sql thread to sync up to
  another position.
  - Added a warning that no more tests should be added at the
  end of the file.
mysql-test/suite/rpl_ndb/r/rpl_ndb_mixed_engines_transactions.result:
  Updated and renamed result file.
mysql-test/suite/rpl_ndb/t/rpl_ndb_mixed_engines_transactions-master.opt:
  No need for the special debug flag any more, it was used by
  the second part of the test which is now in rpl_bug26395.
  Also renamed the file.
mysql-test/suite/rpl_ndb/t/rpl_ndb_mixed_engines_transactions-slave.opt:
  Renamed option file.
mysql-test/suite/rpl_ndb/t/rpl_ndb_mixed_engines_transactions.test:
  - Moved second half of the test to another test (rpl_bug26395)
  - Improved comments.
  - Extended the mixed transaction test to include also innodb.
  - Used 'source include/diff_tables.inc' instead of listing
  several identical tables in the result file.
  - Renamed the test.