@Override
  protected synchronized boolean setTimeoutFailure(MasterProcedureEnv env) {
    setState(ProcedureProtos.ProcedureState.RUNNABLE);
    env.getProcedureScheduler().addFront(this);
    return false;
  }
Base class for replication peer related procedures which do not need to hold locks(for most of
the sub procedures).
hbase-server/src/main/java/org/apache/hadoop/hbase/master/replication/AbstractPeerNoLockProcedure.java