HADOOP-9063. enhance unit-test coverage of class org.apache.hadoop.fs.FileUtil. Contributed by Ivan A. Veselovsky


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1528502 13f79535-47bb-0310-9956-ffa450edef68
YARN-677. Increase coverage to FairScheduler (Vadim Bondarev and Dennis Y via jeagles)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1528524 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5530. Fix compat with hadoop-1 in mapred.lib.CombinFileInputFormat by re-introducing isSplittable(FileSystem, Path) api and ensuring semantic compatibility. Contributed by Robert Kanter.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1528533 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk-gd
Merge remote branch 'origin/trunk-gd' into fb-YAHOO-261-trunk-gd