message: Added comment re:behavior of listener in case of multiple saver hooks.
diff: @@ -732,6 +732,8 @@ class Estimator(object):
  'Please set one of the RunConfig.save_checkpoints_steps or '
  'RunConfig.save_checkpoints_secs.')
  else:
  + # It is expected to have one CheckpointSaverHook. If multiple, we pick
  + # up the first one to add listener.
  saver_hooks[0]._listeners.extend(saving_listeners) # pylint: disable=protected-access
  with training.MonitoredTrainingSession(
  master=self._config.master,
  