Error deleting glance image during unshelve; newer version indexed

During a nova unshelve operation, I noticed the error:

  2016-07-22 11:57:57.600 93579 DEBUG searchlight.elasticsearch.plugins.base [-] Received image.delete event for OS::Glance::Image process /Users/mclellst/openstack/searchlight/searchlight/elasticsearch/plugins/base.py:565 Thread-16
  2016-07-22 11:57:57.604 93579 WARNING searchlight.elasticsearch.plugins.helper [-] Error deleting OS::Glance::Image 85bb16de-40da-4363-954b-71ee6b76682d; newer versions of some documents have been indexed

The image itself seems to have been deleted so this may not be a serious issue but should be investigated further.

To repro, shelve and instance and then unshelve. The shelve operation should result in an image being created; unshelve should delete it. I have been able to repeat the error a couple of times.