Comment 12 for bug 1728028

Reviewed: https://review.opencontrail.org/37244
Committed: http://github.com/Juniper/contrail-controller/commit/5072833960c8f105637cc2e476bda9dc12856ee9
Submitter: Zuul (<email address hidden>)
Branch: R4.1

commit 5072833960c8f105637cc2e476bda9dc12856ee9
Author: Atul Moghe <email address hidden>
Date: Mon Nov 6 23:04:49 2017 -0800

This will read ipam_ref uuid from fq_name if uuid is not in update
message
This will also convert exceptions to str from unicode

In pre_dbe_update, it is not necessary that we will get uuid some time
fq_name is available, in that case we need to use db to retrieve uuid
from the given fq_name
Closes-Bug: #1728028

Change-Id: I5a016bab06a3736e61cf92ed04a4e10525f3cfa6