presto-main/src/main/java/io/prestosql/operator/aggregation/ReduceAggregationFunction.java/ReduceAggregationFunction/combine
class ReduceAggregationFunction:    public static void combine(NullableBooleanState state, NullableBooleanState otherState, BinaryFunctionInterface inputFunction, BinaryFunctionInterface combineFunction)
    {
        if (state.isNull()) {
            state.setNull(false);
            state.setBoolean(otherState.getBoolean());
            return;
        }
        state.setBoolean((boolean) combineFunction.apply(state.getBoolean(), otherState.getBoolean()));
    }