bug: disabling "Allow search only in 1 forum at a time." breaks search.

[T3P3]

If you deselect the check box "Allow search only in 1 forum at a time." in the Features, Search Backstage options search breaks with the following error.

This is with both Luna 2.0.3 and 2.0.7 (just upgraded). With the option checked search works, and obviously searches all the forums and sub forums in our domain. The issue is without this box its not possible to allow advanced search to filter the forums to reduce the search scope.