swift234

SIL: Carry AST types through init_existential instructions.

This is necessary to be able to properly stash values with nontrivial lowerings, such as metatypes and functions, inside existential containers. Modify SILGen to lower values to the proper abstraction level before storing them in an existential container. Part of the fix for rdar://problem/18189508, though runtime problems still remain when trying to actually dynamicCast out a metatype from an Any container.

Swift SVN r21830