It's been introduced in the previous commit
("K2: Simplify handling mixed smartcast vs. original candidates")
Because previously, it was assumed wrongly that each next level of
ConeCallConflictResolver filter out the candidates that are 100% less
applicable/specific, but the main one (ConeOverloadConflictResolver)
either leaves the single candidate or the whole same set, thus at
FilteringOutOriginalInPresenceOfSmartCastConeCallConflictResolver
we've got 4 candidates only two of which we might filter out.
Denis.Zharkov
b4b443034f