swift

e9375109 - Don't consider marker protocols when mangling associated type refs.

Don't consider marker protocols when mangling associated type refs. Associated type references can be mangled without reference to the protocol they are in when there is only one protocol to which the base type conforms. Because marker protocols can never have associated types, don't consider them in this computation. This allows marker protocols to be added more freely to, e.g., generic type requirements. Fixes rdar://95994469.