@Override
        public void doAnAction() throws Exception {
          final String testZnode = parentZnodeName + "/child";
          ZKUtil.createNodeIfNotExistsAndWatch(zkWatcher, testZnode, testZnode.getBytes());
          ZKUtil.deleteNode(zkWatcher, testZnode);
        }
Tests MetaRegionLocationCache's init procedure to make sure that it correctly watches the base
znode for notifications.
hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestMetaRegionLocationCache.java