swift234

Eliminate the old generic-member-substitution path and its support code.

All substitution for generic methods and members of generic classes
now goes through the newer, interface-type-based path. This eliminates
the need for the awful substForBaseConversion() that redid all of the
substitution work already performed by the solver, as well as the
all-archetypes-based substitition encoding code.


Swift SVN r9784