merge MAPREDUCE-5352 from trunk. Optimize node local splits generated by CombineFileInputFormat. (sseth)


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HDFS-4962. Merging change r1501851 from trunk

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svn merge -c 1509389 FIXES: YARN-573. Shared data structures in Public Localizer and Private Localizer are not Thread safe. Contributed by Omkar Vinit Joshi


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