HDFS-5623. NameNode: add tests for skipping ACL enforcement when permission checks are disabled, user is superuser or user is member of supergroup. Contributed by Chris Nauroth.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1571745 13f79535-47bb-0310-9956-ffa450edef68
YARN-1760. TestRMAdminService assumes CapacityScheduler. (kasha)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1571777 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5939. WebHdfs returns misleading error code and logs nothing if trying to create a file with no DNs in cluster. Contributed by Yongjun Zhang.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1571781 13f79535-47bb-0310-9956-ffa450edef68
HDFS-6006. Remove duplicate code in FSNameSystem#getFileInfo. Contributed by Akira Ajisaka.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1571813 13f79535-47bb-0310-9956-ffa450edef68