public T build(DecoratingHttpServiceFunction decoratingHttpServiceFunction) {
        requireNonNull(decoratingHttpServiceFunction, "decoratingHttpServiceFunction");
        return build(delegate -> new FunctionalDecoratingHttpService(delegate, decoratingHttpServiceFunction));
    }
Sets the {@link DecoratingHttpServiceFunction} and returns the context path service builder.

@param decoratingHttpServiceFunction the {@link DecoratingHttpServiceFunction} that decorates
                                     {@link HttpService}
core/src/main/java/com/linecorp/armeria/server/AbstractContextPathDecoratingBindingBuilder.java