notification agent needs to gracefully stop()

run devstack with master branch, and agent-notification prints the following message,

at least, the stop() method of agent-notification should be fixed to correctly call super.stop()

2015-02-06 10:11:07.000 83274 DEBUG ceilometer.pipeline [-] Pipeline config file: None _setup_pipeline_manager /opt/stack/ceilometer/ceilometer/pipeline.py:664
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/eventlet/hubs/hub.py", line 457, in fire_timers
    timer()
  File "/usr/local/lib/python2.7/dist-packages/eventlet/hubs/timer.py", line 58, in __call__
    cb(*args, **kw)
  File "/usr/local/lib/python2.7/dist-packages/eventlet/greenthread.py", line 214, in main
    result = function(*args, **kwargs)
  File "/opt/stack/ceilometer/ceilometer/openstack/common/service.py", line 491, in run_service
    service.start()
  File "/opt/stack/ceilometer/ceilometer/notification.py", line 92, in start
    self.event_pipeline_manager = pipeline.setup_event_pipeline()
  File "/opt/stack/ceilometer/ceilometer/pipeline.py", line 682, in setup_event_pipeline
    return _setup_pipeline_manager(cfg_file, transformer_manager, EVENT_TYPE)
  File "/opt/stack/ceilometer/ceilometer/pipeline.py", line 666, in _setup_pipeline_manager
    with open(cfg_file) as fap:
TypeError: coercing to Unicode: need string or buffer, NoneType found
2015-02-06 10:11:07.001 83274 ERROR ceilometer.openstack.common.threadgroup [-] coercing to Unicode: need string or buffer, NoneType found
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup Traceback (most recent call last):
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup File "/opt/stack/ceilometer/ceilometer/openstack/common/threadgroup.py", line 145, in wait
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup x.wait()
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup File "/opt/stack/ceilometer/ceilometer/openstack/common/threadgroup.py", line 47, in wait
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup return self.thread.wait()
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup File "/usr/local/lib/python2.7/dist-packages/eventlet/greenthread.py", line 175, in wait
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup return self._exit_event.wait()
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup File "/usr/local/lib/python2.7/dist-packages/eventlet/event.py", line 121, in wait
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup return hubs.get_hub().switch()
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup File "/usr/local/lib/python2.7/dist-packages/eventlet/hubs/hub.py", line 294, in switch
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup return self.greenlet.switch()
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup File "/usr/local/lib/python2.7/dist-packages/eventlet/greenthread.py", line 214, in main
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup result = function(*args, **kwargs)
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup File "/opt/stack/ceilometer/ceilometer/openstack/common/service.py", line 491, in run_service
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup service.start()
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup File "/opt/stack/ceilometer/ceilometer/notification.py", line 92, in start
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup self.event_pipeline_manager = pipeline.setup_event_pipeline()
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup File "/opt/stack/ceilometer/ceilometer/pipeline.py", line 682, in setup_event_pipeline
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup return _setup_pipeline_manager(cfg_file, transformer_manager, EVENT_TYPE)
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup File "/opt/stack/ceilometer/ceilometer/pipeline.py", line 666, in _setup_pipeline_manager
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup with open(cfg_file) as fap:
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup TypeError: coercing to Unicode: need string or buffer, NoneType found
2015-02-06 10:11:07.001 83274 TRACE ceilometer.openstack.common.threadgroup
2015-02-06 10:11:07.002 83274 CRITICAL ceilometer [-] AttributeError: 'NotificationService' object has no attribute 'partition_coordinator'
2015-02-06 10:11:07.002 83274 TRACE ceilometer Traceback (most recent call last):
2015-02-06 10:11:07.002 83274 TRACE ceilometer File "/usr/local/bin/ceilometer-agent-notification", line 9, in <module>
2015-02-06 10:11:07.002 83274 TRACE ceilometer load_entry_point('ceilometer==2015.1.dev125', 'console_scripts', 'ceilometer-agent-notification')()
2015-02-06 10:11:07.002 83274 TRACE ceilometer File "/opt/stack/ceilometer/ceilometer/cmd/agent_notification.py", line 28, in main
2015-02-06 10:11:07.002 83274 TRACE ceilometer launcher.wait()
2015-02-06 10:11:07.002 83274 TRACE ceilometer File "/opt/stack/ceilometer/ceilometer/openstack/common/service.py", line 384, in wait
2015-02-06 10:11:07.002 83274 TRACE ceilometer self._respawn_children()
2015-02-06 10:11:07.002 83274 TRACE ceilometer File "/opt/stack/ceilometer/ceilometer/openstack/common/service.py", line 372, in _respawn_children
2015-02-06 10:11:07.002 83274 TRACE ceilometer self._start_child(wrap)
2015-02-06 10:11:07.002 83274 TRACE ceilometer File "/opt/stack/ceilometer/ceilometer/openstack/common/service.py", line 313, in _start_child
2015-02-06 10:11:07.002 83274 TRACE ceilometer status, signo = self._child_wait_for_exit_or_signal(launcher)
2015-02-06 10:11:07.002 83274 TRACE ceilometer File "/opt/stack/ceilometer/ceilometer/openstack/common/service.py", line 271, in _child_wait_for_exit_or_signal
2015-02-06 10:11:07.002 83274 TRACE ceilometer launcher.stop()
2015-02-06 10:11:07.002 83274 TRACE ceilometer File "/opt/stack/ceilometer/ceilometer/openstack/common/service.py", line 125, in stop
2015-02-06 10:11:07.002 83274 TRACE ceilometer self.services.stop()
2015-02-06 10:11:07.002 83274 TRACE ceilometer File "/opt/stack/ceilometer/ceilometer/openstack/common/service.py", line 461, in stop
2015-02-06 10:11:07.002 83274 TRACE ceilometer service.stop()
2015-02-06 10:11:07.002 83274 TRACE ceilometer File "/opt/stack/ceilometer/ceilometer/notification.py", line 204, in stop
2015-02-06 10:11:07.002 83274 TRACE ceilometer self.partition_coordinator.leave_group(self.group_id)
2015-02-06 10:11:07.002 83274 TRACE ceilometer AttributeError: 'NotificationService' object has no attribute 'partition_coordinator'
2015-02-06 10:11:07.002 83274 TRACE ceilometer
2015-02-06 10:11:07.063 83263 INFO ceilometer.openstack.common.service [-] Child 83274 exited with status 1
2015-02-06 10:11:07.063 83263 INFO ceilometer.openstack.common.service [-] Forking too fast, sleeping