swift234

Handle 'self' and nested generics in the interface type of generic functions.

When building the (dependent) interface type of generic functions,
don't resolve any generic parameter types to archetypes, even those at
outer levels. Instead, keep everything dependent.

As a special case, the type of 'self' gets baked into the parameter
patterns with archetypes, so reconstruct the 'self' type ourselves.

The actual output of this is still frustratingly untestable, but we
get decent coverage because all of the type checking of generic
functions goes through here first.



Swift SVN r8936