Return the child logger associated with the specified test UID.

def get_record_logger_for(test_uid):
  """Return the child logger associated with the specified test UID."""
  htf_logger = logging.getLogger(RECORD_LOGGER_PREFIX)
  record_logger = HtfTestLogger('.'.join(((RECORD_LOGGER_PREFIX, test_uid))))
  record_logger.parent = htf_logger
  return record_logger