Audit log in ASYNC mode should not skip log records which don't fit into log buffer

[Sergei Glushchenko]

It wasn't an issue when audit log records were truncated, but it might become an issue.

int audit_log_buffer_write(audit_log_buffer_t *log, const char *buf, size_t len)
{
  if (len > log->size)
    return(1);

has to be replaced with something like

  if (len > log->size)
  {
    if (!log->drop_if_full)
    {
      mysql_mutex_lock(&log->mutex);
      log->write();
      mysql_mutex_unlock(&log->mutex);
    }
    return(0);
  }

[Sergei Glushchenko (sergei.glushchenko)]

https://github.com/percona/percona-server/pull/572

[Sergei Glushchenko (sergei.glushchenko)]

https://github.com/percona/percona-server/pull/925

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PS-988