NPE at at org.opendaylight.netvirt.elan.evpn.utils.EvpnUtils.advertisePrefix while adding and removing elanmacentry

Seen in https://logs.opendaylight.org/releng/jenkins092/netvirt-csit-1node-openstack-newton-nodl-v2-upstream-stateful-carbon/520/archives/odl1_karaf.log.gz

2017-05-10 00:38:48,428 | ERROR | eChangeHandler-0 | AsyncDataTreeChangeListenerBase | 291 - org.opendaylight.genius.mdsalutil-api - 0.2.0.SNAPSHOT | Thread terminated due to uncaught exception: AsyncDataTreeChangeListenerBase-DataTreeChangeHandler-0
java.lang.NullPointerException
at org.opendaylight.netvirt.elan.evpn.utils.EvpnUtils.advertisePrefix(EvpnUtils.java:199)[340:org.opendaylight.netvirt.elanmanager-impl:0.4.0.SNAPSHOT]
at org.opendaylight.netvirt.elan.evpn.listeners.ElanMacEntryListener.add(ElanMacEntryListener.java:66)[340:org.opendaylight.netvirt.elanmanager-impl:0.4.0.SNAPSHOT]
at org.opendaylight.netvirt.elan.evpn.listeners.ElanMacEntryListener.add(ElanMacEntryListener.java:28)[340:org.opendaylight.netvirt.elanmanager-impl:0.4.0.SNAPSHOT]
at org.opendaylight.genius.datastoreutils.AsyncDataTreeChangeListenerBase$DataTreeChangeHandler.run(AsyncDataTreeChangeListenerBase.java:155)[291:org.opendaylight.genius.mdsalutil-api:0.2.0.SNAPSHOT]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)[:1.8.0_121]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)[:1.8.0_121]
at java.lang.Thread.run(Thread.java:745)[:1.8.0_121]