Comment 2 for bug 1556917

Reviewed: https://review.openstack.org/292503
Committed: https://git.openstack.org/cgit/openstack/fuel-web/commit/?id=24647834000c7ac9085f9230d77b6e35396d9a2f
Submitter: Jenkins
Branch: master

commit 24647834000c7ac9085f9230d77b6e35396d9a2f
Author: Aleksey Kasatkin <email address hidden>
Date: Mon Mar 14 18:42:55 2016 +0200

    Robust generating of routes

    'netgroups[ngname]' is replaced with 'netgroups.get(ngname, {})' as
    in other places in serializer.
    Problem was the 'br-prv' endpoint that didn't have IP in case of VLAN
    segmentation. The difference between 'netgroup_mapping' and 'netgroups'
    exists only in case of using network template. Otherwise, absence of IP
    for 'br-prv' did not lead to this issue.

    Also, there is a small refactoring of serialization tests was made here.

    Change-Id: I67616409017631023e707e533cb8e2faab943b34
    Closes-Bug: #1556917