HADOOP-9703.  org.apache.hadoop.ipc.Client leaks threads on stop (Tsuyoshi OZAWA via Colin Patrick McCabe)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1502696 13f79535-47bb-0310-9956-ffa450edef68
Merge remote-tracking branch upstream/$:{upbranch}