Writes a new client startup record.

def WriteClientStartupInfo(self, client_id, startup_info, cursor=None):
    """Writes a new client startup record."""
    query = """
    SET @now = NOW(6);

    INSERT INTO client_startup_history (client_id, timestamp, startup_info)
         VALUES (%(client_id)s, @now, %(startup_info)s);

    UPDATE clients
       SET last_startup_timestamp = @now
     WHERE client_id = %(client_id)s;
    """

    params = {
        "client_id": db_utils.ClientIDToInt(client_id),
        "startup_info": startup_info.SerializeToString(),
    }

    try:
      cursor.execute(query, params)
    except MySQLdb.IntegrityError as e:
      raise db.UnknownClientError(client_id, cause=e)