@Override
    protected FederationSearcher doBuild(DeployState deployState, TreeConfigProducer<AnyConfigProducer> ancestor, Element searcherElement) {
        FederationSearcherModel model = new FederationSearcherModelBuilder(searcherElement).build();
        Optional<Component> targetSelector = buildTargetSelector(deployState, ancestor, searcherElement, model.getComponentId());

        return new FederationSearcher(model, targetSelector);
    }
Builds a federation searcher config producer from an element.

@author Tony Vaagenes
config-model/src/main/java/com/yahoo/vespa/model/builder/xml/dom/chains/search/DomFederationSearcherBuilder.java