Handle volumes no longer existing in resume delete

init_host resumes deletes for volumes with a status of 'deleting'. It
does these sequentially, and sometimes a volume could be deleted under
it, causing a bad stacktrace. This will gracefully handle those
situations and move on. Added coverage for resume volume delete being
successful as well.

Change-Id: I5b30265609b65804f2da77d9daa84b640de7939c
Closes-Bug: #1322340
Merge "Handle volumes no longer existing in resume delete"