DistributedShardedDOMDataTreeRemotingTest.testMultipleRegistrationsAtOnePrefix failing intermittently

DistributedShardedDOMDataTreeRemotingTest.testMultipleRegistrationsAtOnePrefix is failing intermittently in master - seen it twice now. I haven't seen it fail in stable/carbon.

00:49:19 org.opendaylight.controller.cluster.sharding.DOMDataTreeShardCreationFailedException: Unable to create a cds shard.
00:49:19 at org.opendaylight.controller.cluster.sharding.DistributedShardedDOMDataTree$2$2.apply(DistributedShardedDOMDataTree.java:358)
00:49:19 at org.opendaylight.controller.cluster.sharding.DistributedShardedDOMDataTree$2$2.apply(DistributedShardedDOMDataTree.java:355)
00:49:19 at scala.concurrent.Future$$anonfun$transform$1$$anonfun$apply$2.apply(Future.scala:224)
00:49:19 at scala.concurrent.Future$$anonfun$transform$1$$anonfun$apply$2.apply(Future.scala:224)
00:49:19 at scala.util.Try$.apply(Try.scala:192)
00:49:19 at scala.concurrent.Future$$anonfun$transform$1.apply(Future.scala:224)
00:49:19 at scala.concurrent.Future$$anonfun$transform$1.apply(Future.scala:222)
00:49:19 at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:36)
00:49:19 at akka.dispatch.BatchingExecutor$AbstractBatch.processBatch(BatchingExecutor.scala:55)
00:49:19 at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply$mcV$sp(BatchingExecutor.scala:91)
00:49:19 at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply(BatchingExecutor.scala:91)
00:49:19 at akka.dispatch.BatchingExecutor$BlockableBatch$$anonfun$run$1.apply(BatchingExecutor.scala:91)
00:49:19 at scala.concurrent.BlockContext$.withBlockContext(BlockContext.scala:72)
00:49:19 at akka.dispatch.BatchingExecutor$BlockableBatch.run(BatchingExecutor.scala:90)
00:49:19 at akka.dispatch.TaskInvocation.run(AbstractDispatcher.scala:39)
00:49:19 at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:415)
00:49:19 at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
00:49:19 at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
00:49:19 at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
00:49:19 at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
00:49:19 Caused by: org.opendaylight.controller.cluster.sharding.DOMDataTreeShardCreationFailedException: Unable to find the backend shard.Failing..
00:49:19 at org.opendaylight.controller.cluster.sharding.LookupTask.fail(LookupTask.java:50)
00:49:19 at org.opendaylight.controller.cluster.sharding.LookupTask.tryReschedule(LookupTask.java:40)
00:49:19 at org.opendaylight.controller.cluster.sharding.ShardedDataTreeActor$ShardCreationLookupTask$1.onComplete(ShardedDataTreeActor.java:451)
00:49:19 at org.opendaylight.controller.cluster.sharding.ShardedDataTreeActor$ShardCreationLookupTask$1.onComplete(ShardedDataTreeActor.java:447)
00:49:19 at akka.dispatch.OnComplete.internal(Future.scala:258)
00:49:19 at akka.dispatch.OnComplete.internal(Future.scala:256)
00:49:19 at akka.dispatch.japi$CallbackBridge.apply(Future.scala:186)
00:49:19 at akka.dispatch.japi$CallbackBridge.apply(Future.scala:183)
00:49:19 ... 13 more
00:49:19 Caused by: org.opendaylight.controller.cluster.datastore.exceptions.LocalShardNotFoundException: Local shard for test! does not exist.
00:49:19 at org.opendaylight.controller.cluster.datastore.utils.ActorContext$3.checkedApply(ActorContext.java:294)
00:49:19 at org.opendaylight.controller.cluster.datastore.utils.ActorContext$3.checkedApply(ActorContext.java:283)
00:49:19 at akka.dispatch.Mapper.apply(Future.scala:359)
00:49:19 at scala.util.Success$$anonfun$map$1.apply(Try.scala:237)
00:49:19 at scala.util.Try$.apply(Try.scala:192)
00:49:19 at scala.util.Success.map(Try.scala:237)
00:49:19 at scala.concurrent.Future$$anonfun$map$1.apply(Future.scala:237)
00:49:19 at scala.concurrent.Future$$anonfun$map$1.apply(Future.scala:237)
00:49:19 ... 13 more

This is the underlying error:

[ERROR] [05/05/2017 00:47:21.633] [cluster-test-akka.actor.default-dispatcher-4] [akka://cluster-test/user/shardmanager-config] actor name [member-2-shard-test!-config] is not unique!
akka.actor.InvalidActorNameException: actor name [member-2-shard-test!-config] is not unique!
at akka.actor.dungeon.ChildrenContainer$NormalChildrenContainer.reserve(ChildrenContainer.scala:129)
at akka.actor.dungeon.Children$class.reserveChild(Children.scala:130)
at akka.actor.ActorCell.reserveChild(ActorCell.scala:374)
at akka.actor.dungeon.Children$class.makeChild(Children.scala:268)
at akka.actor.dungeon.Children$class.actorOf(Children.scala:42)
at akka.actor.ActorCell.actorOf(ActorCell.scala:374)
at org.opendaylight.controller.cluster.datastore.shardmanager.ShardManager.newShardActor(ShardManager.java:1067)
at org.opendaylight.controller.cluster.datastore.shardmanager.ShardManager.doCreatePrefixShard(ShardManager.java:574)
at org.opendaylight.controller.cluster.datastore.shardmanager.ShardManager.onPrefixShardCreated(ShardManager.java:551)
at org.opendaylight.controller.cluster.datastore.shardmanager.ShardManager.handleCommand(ShardManager.java:258)
at org.opendaylight.controller.cluster.common.actor.AbstractUntypedPersistentActor.onReceiveCommand(AbstractUntypedPersistentActor.java:31)

The test repeats 10 times creating/destroying the "test" shard. It failed on the second round (Round 1). It seem the "test" shard actor from the prior round hadn't been fully destroyed.