Exceptions when Data Store droptest is running

The Data Store droptest does not work anymore, and these exceptions are seen when FRM is trying to write flows into the data store:

java.lang.IllegalArgumentException: Metadata not available for modification [NodeModification [identifier=(urn:opendaylight:inventory?revision=2013-08-19)node[

{(urn:opendaylight:inventory?revision=2013-08-19)id=openflow:13}

], modificationType=SUBTREE_MODIFIED, childModification={(urn:opendaylight:inventory?revision=2013-08-19)node-connector=NodeModification [identifier=(urn:opendaylight:inventory?revision=2013-08-19)node-connector, modificationType=MERGE, childModification={(urn:opendaylight:inventory?revision=2013-08-19)node-connector[

{(urn:opendaylight:inventory?revision=2013-08-19)id=openflow:13:4}

]=NodeModification [identifier=(urn:opendaylight:inventory?revision=2013-08-19)node-connector[

{(urn:opendaylight:inventory?revision=2013-08-19)id=openflow:13:4}

], modificationType=WRITE, childModification={}]}]}]]
at com.google.common.base.Preconditions.checkArgument(Preconditions.java:119) ~[bundlefile:na]
at org.opendaylight.yangtools.yang.data.impl.schema.tree.SchemaAwareApplyOperation.apply(SchemaAwareApplyOperation.java:186) ~[na:na]
at org.opendaylight.yangtools.yang.data.impl.schema.tree.NormalizedNodeContainerModificationStrategy.mutateChildren(NormalizedNodeContainerModificationStrategy.java:132) ~[na:na]
at org.opendaylight.yangtools.yang.data.impl.schema.tree.NormalizedNodeContainerModificationStrategy.applySubtreeChange(NormalizedNodeContainerModificationStrategy.java:163) ~[na:na]
at org.opendaylight.yangtools.yang.data.impl.schema.tree.NormalizedNodeContainerModificationStrategy$UnorderedMapModificationStrategy.applySubtreeChange(NormalizedNodeContainerModificationStrategy.java:311) ~[na:na]
at org.opendaylight.yangtools.yang.data.impl.schema.tree.SchemaAwareApplyOperation.apply(SchemaAwareApplyOperation.java:188) ~[na:na]
at org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeModification.resolveSnapshot(InMemoryDataTreeModification.java:110) ~[na:na]
at org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeModification.readNode(InMemoryDataTreeModification.java:93) ~[na:na]
at org.opendaylight.controller.md.sal.dom.store.impl.SnapshotBackedReadWriteTransaction.read(SnapshotBackedReadWriteTransaction.java:58) ~[bundlefile:na]
at org.opendaylight.controller.md.sal.dom.broker.impl.DOMForwardedReadWriteTransaction.read(DOMForwardedReadWriteTransaction.java:51) [bundlefile:na]
at org.opendaylight.controller.md.sal.binding.impl.AbstractForwardedTransaction.doRead(AbstractForwardedTransaction.java:63) [bundlefile:na]
at org.opendaylight.controller.md.sal.binding.impl.BindingDataReadWriteTransactionImpl.read(BindingDataReadWriteTransactionImpl.java:31) [bundlefile:na]
at org.opendaylight.controller.md.inventory.manager.NodeChangeCommiter$4.applyOperation(NodeChangeCommiter.java:117) [bundlefile:na]
at org.opendaylight.controller.md.inventory.manager.FlowCapableInventoryProvider.run(FlowCapableInventoryProvider.java:93) [bundlefile:na]
at java.lang.Thread.run(Thread.java:745) [na:1.7.0_65]
2014-08-17 01:41:01.330 PDT [FlowCapableInventoryProvider] ERROR o.o.y.y.d.i.s.t.InMemoryDataTreeModification - Could not create snapshot for (urn:opendaylight:inventory?revision=2013-08-19)nodes/(urn:opendaylight:inventory?revision=2013-08-19)node/(urn:opendaylight:inventory?revision=2013-08-19)node[

{(urn:opendaylight:inventory?revision=2013-08-19)id=openflow:13}

]:NodeModification [identifier=(urn:opendaylight:inventory?revision=2013-08-19)node[

{(urn:opendaylight:inventory?revision=2013-08-19)id=openflow:13}

], modificationType=SUBTREE_MODIFIED, childModification={(urn:opendaylight:inventory?revision=2013-08-19)node-connector=NodeModification [identifier=(urn:opendaylight:inventory?revision=2013-08-19)node-connector, modificationType=MERGE, childModification={(urn:opendaylight:inventory?revision=2013-08-19)node-connector[

{(urn:opendaylight:inventory?revision=2013-08-19)id=openflow:13:4}

]=NodeModification [identifier=(urn:opendaylight:inventory?revision=2013-08-19)node-connector[

{(urn:opendaylight:inventory?revision=2013-08-19)id=openflow:13:4}

], modificationType=WRITE, childModification={}]}]}]

To reproduce, simply run the cbench test with the Data Store loopback turned on (dropAllPackets on)