DataTree: properly report wrong instance identifiers

Using a wrong instance identifier in delete operation will result in the following:

2015-04-07 14:06:46,768 | ERROR | DOM-OPER-DCL-8 | QueuedNotificationManager | 78 - org.opendaylight.yangtools.util - 0.7.0.SNAPSHOT | DataTreeChangeListenerQueueMgr: Error notifying listener AbstractObjectRegistration

{instance= org.opendaylight.protocol.bgp.rib.impl.LocRibWriter@6b34c205}

com.google.common.cache.CacheLoader$InvalidCacheLoadException: CacheLoader returned null for key (urn:opendaylight:params:xml:ns:yang:bgp-inet?revision=2015-03-05)ipv4-route[

{(urn:opendaylight:params:xml:ns:yang:bgp-inet?revision=2015-03 -05)prefix=204.20.160.41/32}

].
at com.google.common.cache.LocalCache$Segment.getAndRecordStats(LocalCache.java:2350)[75:com.google.guava:18.0.0]
at com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2320)[75:com.google.guava:18.0.0]
at com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2282)[75:com.google.guava:18.0.0]
at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2197)[75:com.google.guava:18.0.0]
at com.google.common.cache.LocalCache.get(LocalCache.java:3937)[75:com.google.guava:18.0.0]
at com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:3941)[75:com.google.guava:18.0.0]
at com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4824)[75:com.google.guava:18.0.0]
at org.opendaylight.yangtools.yang.data.impl.schema.tree.AbstractDataNodeContainerModificationStrategy.getChild(AbstractDataNodeContainerModificationStrategy.java:60)[113:org.opendaylight.yangtools.yang-data-impl:0.7.0.SNAPSHOT]
at org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeModification.resolveModificationFor(InMemoryDataTreeModification.java:150)[113:org.opendaylight.yangtools.yang-data-impl:0.7.0.SNAPSHOT]
at org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeModification.delete(InMemoryDataTreeModification.java:81)[113:org.opendaylight.yangtools.yang-data-impl:0.7.0.SNAPSHOT]
at org.opendaylight.controller.md.sal.dom.store.impl.SnapshotBackedWriteTransaction.delete(SnapshotBackedWriteTransaction.java:109)[182:org.opendaylight.controller.sal-inmemory-datastore:1.2.0.SNAPSHOT]
at org.opendaylight.controller.md.sal.dom.broker.impl.DOMForwardedWriteTransaction.delete(DOMForwardedWriteTransaction.java:96)[176:org.opendaylight.controller.sal-broker-impl:1.2.0.SNAPSHOT]
at org.opendaylight.controller.md.sal.dom.broker.impl.DOMForwardedWriteTransaction.delete(DOMForwardedWriteTransaction.java:51)[176:org.opendaylight.controller.sal-broker-impl:1.2.0.SNAPSHOT]
at org.opendaylight.protocol.bgp.rib.impl.LocRibWriter.onDataTreeChanged(LocRibWriter.java:188)[189:org.opendaylight.bgpcep.bgp-rib-impl:0.4.0.SNAPSHOT]
at org.opendaylight.controller.md.sal.dom.store.impl.InMemoryDOMStoreTreeChangePublisher$1.invokeListener(InMemoryDOMStoreTreeChangePublisher.java:33)[182:org.opendaylight.controller.sal-inmemory-datastore:1.2.0.SNAPSHOT]
at org.opendaylight.controller.md.sal.dom.store.impl.InMemoryDOMStoreTreeChangePublisher$1.invokeListener(InMemoryDOMStoreTreeChangePublisher.java:27)[182:org.opendaylight.controller.sal-inmemory-datastore:1.2.0.SNAPSHOT]
at org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager$NotificationTask.notifyListener(QueuedNotificationManager.java:411)[78:org.opendaylight.yangtools.util:0.7.0.SNAPSHOT]
at org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager$NotificationTask.run(QueuedNotificationManager.java:382)[78:org.opendaylight.yangtools.util:0.7.0.SNAPSHOT]
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)[:1.7.0_67]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)[:1.7.0_67]
at java.lang.Thread.run(Unknown Source)[:1.7.0_67]

Which does not identify the cause (user error), but looks as though the problem is in the yangtools code.