HADOOP-10404. Some accesses to DomainSocketWatcher#closed are not protected by the lock (cmccabe)
(cherry picked from commit 8099de259fb91a29674bf17cb1382c038b707a90)
HADOOP-10404.  Commit correct version of patch (cmccabe)
(cherry picked from commit 687d83c9e10a4432c8d54c2cd406c7ccb4392187)
HDFS-7194 Fix findbugs "inefficient new String constructor" warning in DFSClient#PATH (yzhang via cmccabe)
(cherry picked from commit 8dc6abf2f4218b2d84b2c2dc7d18623d897c362d)
YARN-2644. Fixed CapacityScheduler to return up-to-date headroom when AM allocates. Contributed by Craig Welch
(cherry picked from commit 519e5a7dd2bd540105434ec3c8939b68f6c024f8)