public void addMutateOperation(MutateOperation op) {
        mutateOperations.add(op);
        String prefix = "vespa.mutate." + op.phase.toString();
        addRankProperty(prefix + ".attribute", op.attribute);
        addRankProperty(prefix + ".operation", op.operation);
    }
Returns the inputs of this, which also includes all inputs of the parents of this.
config-model/src/main/java/com/yahoo/schema/RankProfile.java