merge MAPREDUCE-4693 from trunk. Historyserver should include counters for failed tasks. Contributed by Xuan Gong.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1450957 13f79535-47bb-0310-9956-ffa450edef68
svn merge -r 1450962:1450963 Merging from trunk to branch-2 to fix HADOOP-9339

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1450966 13f79535-47bb-0310-9956-ffa450edef68
Typo in CHANGES.txt for HADOOP-9339

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1450971 13f79535-47bb-0310-9956-ffa450edef68