When combining filters, the old logic assumed that every filter was
exclusive, unless that filter contained multiple items, in which
case it was added to a list of "or" filters that returned all
matching flags.
A fault was discovered in that if you passed in multiple "or"
states, it did not return flags with the expected filtering.
e.g. open flags, closed flags, flags of cid 1, flags of cid 2
This could return open flags of cid 3, since all of the filters
were "OR"'d.
This logic change updates the behaviour so disparate OR sets are
intersected (ANDed).
1603566bcc