celery/kombu — pull request #273 by victorgp (2013-11-13 16:07:53+00:00)
Title: fixing small bug in prepare_message method: type object argument after *...

...* must be a mapping, not NoneType

The "properties" params is passed with ** so it can't be None, just using {} if None to avoid error:

type object argument after ** must be a mapping, not NoneType