ConformanceLookup: filter ReferenceStorageType

There's a few uses of ReferenceStorageTypes being substituted for
generic parameters, at least in the test suite, such as
`Optional<@sil_unmanaged ..>` and just plain `<@sil_unowned ..>`.

Before, conformance lookup could (and did) give bogus answers when asked
 if the type satisfies any conformance requirements. Now with
 NoncopyableGenerics, we will interpret such conformance lookups as
 being asked of the referent type, ignoring the SIL ownership wrapping
 it.

Author: kavon

lib/AST/ConformanceLookup.cpp

@@ -472,6 +472,9 @@ LookupConformanceInModuleRequest::evaluate(
   auto *protocol = desc.PD;
   ASTContext &ctx = mod->getASTContext();
 
+  // Remove SIL reference ownership wrapper, if present.
+  type = type->getReferenceStorageReferent();
+
   // A dynamic Self type conforms to whatever its underlying type
   // conforms to.
   if (auto selfType = type->getAs<DynamicSelfType>())

lib/Sema/TypeCheckType.cpp

@@ -1083,14 +1083,6 @@ Type TypeResolution::applyUnboundGenericArguments(
   if (didDiagnoseMoveOnlyGenericArgs(ctx, loc, resultType, genericArgs, dc))
     return ErrorType::get(ctx);
 
-  if (options.contains(TypeResolutionFlags::SILType)) {
-    if (auto nominal = dyn_cast<NominalTypeDecl>(decl)) {
-      if (nominal->isOptionalDecl()) {
-        skipRequirementsCheck = true;
-      }
-    }
-  }
-
   // Get the substitutions for outer generic parameters from the parent
   // type.
   if (parentTy) {