Problem:
========
When using mariadb-binlog with --raw and --stop-never, events from
the master's currently active log file should be written to their
respective log file specified by --result-file, and shown on-disk.
There is a bug where mariadb-binlog does not flush the result file
to disk when new events are received

Solution:
========
Add a function call to flush mariadb-binlog’s result file after
receiving an event in --raw mode.

Reviewed By:
============
Andrei Elkin <andrei.elkin@mariadb.com>