@Override
    public void nodeDeleted(String path) {
      if (path.equals(node)) {
        LOG.debug("nodeDeleted(" + path + ")");
        lock.release();
      }
    }
Assert there is an active master and that it has the specified address.
@param zk              single Zookeeper watcher
@param expectedAddress the expected address of the master
@throws KeeperException unexpected Zookeeper exception
@throws IOException     if an IO problem is encountered
hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestActiveMasterManager.java