presto-main/src/main/java/io/prestosql/sql/planner/plan/WindowNode.java/WindowNode/replaceChildren
class WindowNode:    @Override
    public PlanNode replaceChildren(List<PlanNode> newChildren)
    {
        return new WindowNode(getId(), Iterables.getOnlyElement(newChildren), specification, windowFunctions, hashSymbol, prePartitionedInputs, preSortedOrderPrefix);
    }