swift234

ConformanceLookupTable: Recursively inherit into subclasses when incrementally adding extension conformances.

Previously, we would only reliably propagate conformances from new extensions to immediate subclasses, since when we visit grandchild classes, we'd see no change in the immediate base class's status. Fix this by walking up the entire superclass chain when we look for new inherited conformances, and track the last processed state of different nominal type decls' extensions separately. Fixes SR-1480.