HDFS-7340. Make rollingUpgrade start/finalize idempotent. Contributed by Jing Zhao.
HDFS-7334. Fix periodic failures of TestCheckpoint#testTooManyEditReplayFailures. Contributed by Charles Lamb.
HDFS-7355. TestDataNodeVolumeFailure#testUnderReplicationAfterVolFailure fails on Windows, because we cannot deny access to the file owner. Contributed by Chris Nauroth.
YARN-2752. Made ContainerExecutor append "nice -n" arg only when priority adjustment flag is set. Contributed by Xuan Gong.

(cherry picked from commit e06c23a6c92ef783cdb45447fa2abd1ab48d166f)
HDFS-7233. NN logs unnecessary org.apache.hadoop.hdfs.protocol.UnresolvedPathException. Contributed by Rushabh S Shah.
HADOOP-11260. Patch up Jetty to disable SSLv3. (Mike Yoder via kasha)

(cherry picked from commit dbf30e3c0e1522e6588aecac71c990c0b01fd8fb)
Adding release 2.5.2 to CHANGES.txt

(cherry picked from commit 4de56d27fbed566f143b286aa74b16ef94260190)

Conflicts:
	hadoop-yarn-project/CHANGES.txt
YARN-2010. Handle app-recovery failures gracefully. (Jian He and Karthik Kambatla via kasha)

(cherry picked from commit b2cd2698028118b6384904732dbf94942f644732)
YARN-2804. Fixed Timeline service to not fill the logs with JAXB bindings exceptions. Contributed by Zhijie Shen.

(cherry picked from commit b76179895dd2ef4d56e8de31e9f673375faa2afa)

Conflicts:
	hadoop-yarn-project/CHANGES.txt
MAPREDUCE-6048. Fixed TestJavaSerialization failure. Contributed by Varun Vasudev
(cherry picked from commit 73068f677bc45029743ba2e0b3c0256a8069c13e)
HDFS-7218. FSNamesystem ACL operations should write to audit log on failure. (clamb via yliu)