@Override
    public Result search(Query query, Execution execution) {
        Result result = execution.search(query);

        query.trace(false, 3, simpleName, " updating headers.");
        keepAliveProcessing(query, result);
        return result;
    }
Create a searcher instance suitable for unit tests.

@param clock a simulated or real clock behaving similarly to System.currentTimeMillis()
@return a fully initialised instance
container-search/src/main/java/com/yahoo/search/searchers/ConnectionControlSearcher.java