private SearchChain dummySearchChain() {
            return new SearchChain(new ComponentId("child-chain"),
                    new DummySearcher(new ComponentId("child-searcher")) {});
        }
A search chain consisting of two searchers.
@author bratseth
@author Tony Vaagenes
container-search/src/test/java/com/yahoo/search/searchchain/test/SimpleSearchChain.java