HADOOP-10482. Fix various findbugs warnings in hadoop-common. Contributed by Haohui Mai.
HADOOP-11388. Remove deprecated o.a.h.metrics.file.FileContext. Contributed by Li Lu.
HADOOP-11386. Replace \n by %n in format hadoop-common format strings. Contributed by Li Lu.
HDFS-5578. [JDK8] Fix Javadoc errors caused by incorrect or illegal tags in doc comments. Contributed by Andrew Purtell.
HDFS-7475. Make TestLazyPersistFiles#testLazyPersistBlocksAreSaved deterministic. (Contributed by Xiaoyu Yao)
MAPREDUCE-5420. Remove mapreduce.task.tmp.dir from mapred-default.xml. Contributed by James Carman. (harsh)

(cherry picked from commit cb99f43305bd1577d4ba9527d237ac6cdb9ae730)
HDFS-7463. Simplify FSNamesystem#getBlockLocationsUpdateTimes. Contributed by Haohui Mai.
HDFS-7503. Namenode restart after large deletions can cause slow processReport (Arpit Agarwal)
Merge remote-tracking branch 'remotes/origin/branch-2' into branch-2