YARN-1078. Merging change r1522644 from trunk to branch-2.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1522645 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-9958. Add old constructor back to DelegationTokenInformation to unbreak downstream builds. (Andrew Wang)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1522709 13f79535-47bb-0310-9956-ffa450edef68