[MONDRIAN-1694]  Since a native filter can be used even when the context is not NON EMPTY, the cache key needs to include NON EMPTY state.  Otherwise the resulting tuple
list may not correctly reflect isNonEmpty.
(cherry picked from commit ab32ceb)
Merge pull request #204 from mkambol/lagMon1694

[MONDRIAN-1694]  Since a native filter can be used even when the context...