fake_notifier.wait_for_versioned_notifications previously returned
None if it timed out. This is counter-intuitive, and several callers
were failing to check its return. Every one of these represents a race
as it means we can continue past a barrier without its condition
having been met.
This change makes it default to safe by raising an exception if it
times out. Note that it's possible this may subsequently result in new
non-deterministic errors in functional. I would consider this a
feature, as these were previously hidden. They should be addressed
individually.
This change highlights several deterministically incorrect uses of
wait_for_versioned_notifications which were previously always silently
timing out. These are all fixed.
We also increase the default timeout from 1 to 10 seconds as we seem
to hit the 1 second timeout in practise, e.g.:
http://logs.openstack.org/46/578846/14/check/nova-tox-functional/8a444c1/job-output.txt.gz
Change-Id: I017d1a31139c9300642dd706eadc265f7c954ca8
c333e7e12e