swift234

Diagnose attempts to both delegate to a peer and chain to a superclass initializer.

While we're here, cache the result of looking for delegation or
chaining calls within ConstructorDecl. Only Sema and SILGen for the
body of the constructor care, so we don't serialize this
information. Rather, we have a faster-path to recompute it should
someone ask again after it was cached.


Swift SVN r11969