Comment 19 for bug 1443318

Reviewed: https://review.opencontrail.org/10336
Committed: http://github.org/Juniper/contrail-controller/commit/ce36b77733fff8b4837b031ff73a9866299aaf18
Submitter: Zuul
Branch: R2.20

commit ce36b77733fff8b4837b031ff73a9866299aaf18
Author: Manish <email address hidden>
Date: Tue Apr 28 16:55:31 2015 +0530

Tor agent crashes during addition of multicast route.

Problem:
When VN to VRF link is not present addition of multicast route in tor agent
used to crash as addition routine tries to access VN name from VRF entry.
Absence of link used to return NULL VN and accessing it for VN name
results in crash.

Solution:
Use VN name from VN OVSDB entry. Pass it along in API.
Multicast OVSDB does not gets resolved till VN OVSDB is resolved,
hence using VN name from same is safe.

Conflicts:
 src/vnsw/agent/oper/vn.cc
 src/vnsw/agent/oper/vn.h
 src/vnsw/agent/test/test_util.cc

Closes-bug: 1443318
(cherry picked from commit a904a762c801ce4a6dd483c33b96d60ec5891606)

Change-Id: Ic4d4949ee69bf811bca426e7d324c6b64d4330a9