Be nice when there is a null body in ThriftEventAdapter

Sometimes we get this null pointer exception from thrift generated events:

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10/12/27 18:57:48 ERROR connector.DirectDriver: Driving src/sink failed! LazyOpenSource | LazyOpenDecorator because null
java.lang.NullPointerException
at com.cloudera.flume.handlers.thrift.ThriftEventAdaptor.getBody(ThriftEventAdaptor.java:50)
at com.cloudera.flume.core.EventSource$Base.updateEventProcessingStats(EventSource.java:147)
at com.cloudera.flume.handlers.thrift.ThriftEventSource.next(ThriftEventSource.java:217)
at com.cloudera.flume.collector.CollectorSource.next(CollectorSource.java:71)
at com.cloudera.flume.handlers.debug.LazyOpenSource.next(LazyOpenSource.java:54)
at com.cloudera.flume.core.connector.DirectDriver$PumperThread.run(DirectDriver.java:89)

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alexvk:

This is in DFO mode, and BE mode using agentDFOChain and agentBEChain.
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happens in BE mode as well...
4:20 PMHsieh, Jonathan
how did you get here?
4:22 PMKozlov, Alex
Configured xxx.comm via `flume shell`, killed both collectors, and restarted 'em
4:32 PMHsieh, Jonathan
This is strange. I could add a check and a WARN to make it not stop, but something strange may have happened on the sender side.
""""