[cxx-interop] fix how we import CF types.

Author: zoecarver

lib/ClangImporter/ClangImporter.cpp

@@ -2757,7 +2757,7 @@ ClangImporter::Implementation::lookupTypedef(clang::DeclarationName name) {
                                    clang::SourceLocation(),
                                    clang::Sema::LookupOrdinaryName);
 
-  if (sema.LookupName(lookupResult, /*scope=*/nullptr)) {
+  if (sema.LookupName(lookupResult, sema.TUScope)) {
     for (auto decl : lookupResult) {
       if (auto typedefDecl =
           dyn_cast<clang::TypedefNameDecl>(decl->getUnderlyingDecl()))

test/ClangImporter/cf.swift

@@ -1,5 +1,7 @@
 // RUN: %target-swift-frontend -disable-objc-attr-requires-foundation-module -typecheck -verify -import-cf-types -I %S/Inputs/custom-modules %s
 
+// RUN: %target-swift-frontend -disable-objc-attr-requires-foundation-module -typecheck -verify -import-cf-types -enable-experimental-cxx-interop -I %S/Inputs/custom-modules %s
+
 // REQUIRES: objc_interop
 
 import CoreCooling