swift234

IRGen: Tweak witness 'This' binding to allow class-bounded archetypes.

Handle the case of a 'this' parameter of 'This' type not being an LValueType or MetaTypeType, which happens for class-bounded protocols. This gets witness emission working for class-bounded archetypes.

Some abstraction remapping still needs to be implemented when non-class-bounded methods are accessed from a class-bounded archetype with a mix of class-bounded and non-class-bounded protocol constraints, to remap the class-bounded archetype to its opaque representation.

Swift SVN r5573