NullPointerException at org.opendaylight.netvirt.neutronvpn.NeutronvpnManager.deleteVpnInterface

Found in CSIT: https://logs.opendaylight.org/releng/jenkins092/netvirt-csit-1node-openstack-mitaka-upstream-transparent-boron/69/archives/odl1_karaf.log.gz

2016-12-14 14:03:24,306 | ERROR | nPool-1-worker-1 | DataStoreJobCoordinator | 281 - org.opendaylight.genius.mdsalutil-api - 0.1.2.SNAPSHOT | Exception when executing jobEntry: JobEntry

{key='PORT-5b0e66e0-a05a-4739-a6c6-68e3b2b1ccec', mainWorker=org.opendaylight.netvirt.neutronvpn.NeutronvpnManager$$Lambda$155/1524762708@44b44c6a, rollbackWorker=null, retryCount=0, futures=null}

java.lang.NullPointerException
at org.opendaylight.netvirt.neutronvpn.NeutronvpnManager.deleteVpnInterface(NeutronvpnManager.java:663)
at org.opendaylight.netvirt.neutronvpn.NeutronvpnManager.lambda$removeSubnetFromVpn$0(NeutronvpnManager.java:1538)
at org.opendaylight.genius.datastoreutils.DataStoreJobCoordinator$MainTask.run(DataStoreJobCoordinator.java:254)[281:org.opendaylight.genius.mdsalutil-api:0.1.2.SNAPSHOT]
at java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec(ForkJoinTask.java:1402)[:1.8.0_111]
at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)[:1.8.0_111]
at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)[:1.8.0_111]
at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)[:1.8.0_111]
at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)[:1.8.0_111]