Fake rummager should handle nil field values gracefully

By coincidence we hadn't hit this scenario in tests until now.
Don't filter by local government relevance unless requested

The previous implementation would mistakenly hide local government
content if the checkbox was unchecked, and show it if it was checked.

However, the intention is that you could request only local government
content if desired by checking the box, and otherwise you would see
everything.

https://www.pivotaltracker.com/story/show/44806697