AMBARI-2159. After upgrading ambari from 1.2.2.5 to 1.2.3.6 the server throws 500 error when starting/stopping any service. (smohanty)

git-svn-id: https://svn.apache.org/repos/asf/incubator/ambari/trunk@1485518 13f79535-47bb-0310-9956-ffa450edef68