public void setPredicateExpression(VectorExpression predicateExpression) {
    this.predicateExpression = predicateExpression;
  }
VectorFilterDesc.

Extra parameters beyond FilterDesc just for the VectorFilterOperator.

We don't extend FilterDesc because the base OperatorDesc doesn't support
clone and adding it is a lot work for little gain.
ql/src/java/org/apache/hadoop/hive/ql/plan/VectorFilterDesc.java