MAPREDUCE-5084. fix coverage org.apache.hadoop.mapreduce.v2.app.webapp and org.apache.hadoop.mapreduce.v2.hs.webapp (Aleksey Gorshkov via jeagles)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23@1494695 13f79535-47bb-0310-9956-ffa450edef68
Clean up an IPC error message. Contributed by Aaron T. Myers.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23@1494701 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/branch-0.23' into branch-0.23-gd
Merge remote branch 'origin/branch-0.23-gd' into fb-xxx-hadoop-auth-kerberos-realm-branch-0.23-gd