MAPREDUCE-5770. Fixed MapReduce ApplicationMaster to correctly redirect to the YARN's web-app proxy with the correct scheme prefix. Contributed by Jian He.
svn merge --ignore-ancestry -c 1572711 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1572712 13f79535-47bb-0310-9956-ffa450edef68