Update ref used for notifications

When we update a volume status in the db, we need to
use the newly updated volume-ref object in the following
notification method call.  Otherwise we're sending a
notification message with the old/outdated status
information.

Change-Id: I4d92b340cf5e20aaa885377dfb6bd6fc4ed87d69
Closes-Bug: #1349808
Merge "Update ref used for notifications"