NPE when accessing a mount point from a different node

odl: distribution-karaf-0.6.0-20161202.174528-2268.zip

steps to reproduce:

• configure test device which is connected to one of the cluster node
• try GET towards all 3 nodes if the mountpoint is visible

2016-12-02 18:54:41,212 | ERROR | on-dispatcher-67 | DataTreeChangeListenerActor | 202 - org.opendaylight.controller.sal-clustering-commons - 1.5.0.SNAPSHOT | Error notifying listener org.opendaylight.controller.md.sal.binding.impl.BindingClusteredDOMDataTreeChangeListenerAdapter@5196aaaf
java.lang.NullPointerException
at org.opendaylight.netconf.topology.singleton.impl.NetconfNodeManager.handleSlaveMountPoint(NetconfNodeManager.java:122)[530:org.opendaylight.netconf.topology-singleton:1.2.0.SNAPSHOT]
at org.opendaylight.netconf.topology.singleton.impl.NetconfNodeManager.onDataTreeChanged(NetconfNodeManager.java:71)[530:org.opendaylight.netconf.topology-singleton:1.2.0.SNAPSHOT]
at org.opendaylight.controller.md.sal.binding.impl.BindingDOMDataTreeChangeListenerAdapter.onDataTreeChanged(BindingDOMDataTreeChangeListenerAdapter.java:41)[169:org.opendaylight.controller.sal-binding-broker-impl:1.5.0.SNAPSHOT]
at org.opendaylight.controller.cluster.datastore.DataTreeChangeListenerActor.dataChanged(DataTreeChangeListenerActor.java:54)[208:org.opendaylight.controller.sal-distributed-datastore:1.5.0.SNAPSHOT]
at org.opendaylight.controller.cluster.datastore.DataTreeChangeListenerActor.handleReceive(DataTreeChangeListenerActor.java:35)[208:org.opendaylight.controller.sal-distributed-datastore:1.5.0.SNAPSHOT]
at org.opendaylight.controller.cluster.common.actor.AbstractUntypedActor.onReceive(AbstractUntypedActor.java:28)[202:org.opendaylight.controller.sal-clustering-commons:1.5.0.SNAPSHOT]
at akka.actor.UntypedActor$$anonfun$receive$1.applyOrElse(UntypedActor.scala:165)[182:com.typesafe.akka.actor:2.4.11]
at akka.actor.Actor$class.aroundReceive(Actor.scala:484)[182:com.typesafe.akka.actor:2.4.11]
at akka.actor.UntypedActor.aroundReceive(UntypedActor.scala:95)[182:com.typesafe.akka.actor:2.4.11]
at akka.actor.ActorCell.receiveMessage(ActorCell.scala:526)[182:com.typesafe.akka.actor:2.4.11]
at akka.actor.ActorCell.invoke(ActorCell.scala:495)[182:com.typesafe.akka.actor:2.4.11]
at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:257)[182:com.typesafe.akka.actor:2.4.11]
at akka.dispatch.Mailbox.run(Mailbox.scala:224)[182:com.typesafe.akka.actor:2.4.11]
at akka.dispatch.Mailbox.exec(Mailbox.scala:234)[182:com.typesafe.akka.actor:2.4.11]
at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)[177:org.scala-lang.scala-library:2.11.8.v20160304-115712-1706a37eb8]
at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)[177:org.scala-lang.scala-library:2.11.8.v20160304-115712-1706a37eb8]
at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)[177:org.scala-lang.scala-library:2.11.8.v20160304-115712-1706a37eb8]
at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)[177:org.scala-lang.scala-library:2.11.8.v20160304-115712-1706a37eb8]