309d9974_orter_plugin_for_MR___ASF_JIRA__Reason
[Class] org.apache.hadoop.mapred.Task.CombinerRunner [Protection] Changed from protected to public [Annotation] Changed from Private, Unstable to Public, Unstable [Reason] 
For code reuse to run the Combiner from external PostMapProcessor plug-ins.
[MAPREDUCE-2454] Allow external sorter plugin for MR - ASF JIRA