oslo.messaging 'dictionary changed size during iteration'

[Mark McLoughlin]

From:

  http://logs.openstack.org/08/42208/2/gate/gate-oslo.messaging-python27/14b3d17/console.html

   File "/home/jenkins/workspace/gate-oslo.messaging-python27/tests/test_rabbit.py", line 168, in send_and_wait_for_reply
     timeout=self.timeout))
   File "/home/jenkins/workspace/gate-oslo.messaging-python27/.tox/py27/local/lib/python2.7/site-packages/oslo/messaging/_drivers/amqpdriver.py", line 353, in send
     return self._send(target, ctxt, message, wait_for_reply, timeout)
   File "/home/jenkins/workspace/gate-oslo.messaging-python27/.tox/py27/local/lib/python2.7/site-packages/oslo/messaging/_drivers/amqpdriver.py", line 344, in _send
     result = self._waiter.wait(msg_id, timeout)
   File "/home/jenkins/workspace/gate-oslo.messaging-python27/.tox/py27/local/lib/python2.7/site-packages/oslo/messaging/_drivers/amqpdriver.py", line 227, in wait
     self.waiters.wake_all(msg_id)
   File "/home/jenkins/workspace/gate-oslo.messaging-python27/.tox/py27/local/lib/python2.7/site-packages/oslo/messaging/_drivers/amqpdriver.py", line 118, in wake_all
     msg_ids = [i for i in self._queues if i != except_id]
 RuntimeError: dictionary changed size during iteration

See the fix for a similar issue here: https://review.openstack.org/39867

[Davanum Srinivas (DIMS) (dims-v)]

Fixed in https://review.openstack.org/#/c/42501/