Comment 3 for bug 1681083

Reviewed: https://review.opencontrail.org/30883
Committed: http://github.com/Juniper/contrail-controller/commit/576a857032cf50c8a134e247f69de0ef99fbbce8
Submitter: Zuul (<email address hidden>)
Branch: master

commit 576a857032cf50c8a134e247f69de0ef99fbbce8
Author: Manish <email address hidden>
Date: Mon May 1 00:40:57 2017 +0530

VRF deletetimeout

Problem:
Fix for bug#1666139 broke code where mpls label change handling for fmg.
Old fabric label can not be reliably picked from fmg path. It can be only picked
from multicast master path. Solution should take care of this point along with
not breaking 1666139.

Solution:
Pick up old fmg label as done prior to fix of 1666139, but check for reserved
fmg label to identify if multicast path is having evpn or fmg label.

Change-Id: I056b61867498f6ec83c11babc2b6aaabcc09a3e9
Closes-bug: #1681083