Don't throw an error when using PropertyInListExpression and an empty list

[caseycesari]

If you provide PropertyInListExpression with an empty list, NetDAO throws an error

Cannot query for {{ insert field name here }} values in an empty list.

In my case, I'm generating the list dynamically, and sometimes it may be empty. Current workarounds are to 1) populate the list with a -1 if the list is empty, or 2) not add the criteria if the list is empty.