MAPREDUCE-4969. Merge change 1441069 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1441070 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4451. Merge change 1441113 and 1441123 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1441128 13f79535-47bb-0310-9956-ffa450edef68
Merge branch 'branch-2' of github.com:griddynamics/yhadoop-common into branch-2-gd
Merge branch 'branch-2-gd' of github.com:griddynamics/yhadoop-common into fb-YAHOO-159-branch-2-gd