In 10.0, VIO timeouts can be in milliseconds, so we add a new function
mysql_get_timeout_value_ms() which can return millisecond-precision
timeout values.

In 5.5, we do not have millisecond precision for timeouts. But we still
provide the mysql_get_timeout_value_ms() function; this makes it easier
for applications as they can use the millisecond function in 10.0 and
still work with the 5.5 version of the client library.