swift234

Update existing block shims for UncheckedOptional.

These are both past mistakes from me. One is a case of me missing the
OBJCPTR macro (which adds the UncheckedOptional bit); the other is a case
of including it when the block is actually written in Swift (and thus uses
a non-optional string).

<rdar://problem/16519094&16513659>

Swift SVN r15915