@Override
        public boolean visit(Item item) {
            if (item instanceof PredicateQueryItem) {
                visit((PredicateQueryItem) item);
            }
            if (item instanceof SimpleIndexedItem) {
                visit((SimpleIndexedItem) item);
            }
            return true;
        }
Checks that predicate queries don't use values outside the defined upper/lower bounds.

@author Magnar Nedland
container-search/src/main/java/com/yahoo/prelude/searcher/ValidatePredicateSearcher.java