swift

968f350d - ASTMangler: skip mangling Copyable dependents

ASTMangler: skip mangling Copyable dependents Typically, a conformance that is dependent on a conformance to a marker protocol never reaches this point in the compiler, where we're mangling the metadata for an opaque return type. But with the invertible protocols like Copyable, we do permit them, so we should avoid mangling Copyable as that's generally ABI incompatible with existing code. resolves rdar://135310019 (cherry picked from commit 6f6a46f225d29459f66e3e052c2ca33183cdb650)