[Concurrency] Fix how we obtain DA-as-A conformance for cross module

Resolves rdar://127206143

lib/Sema/CodeSynthesisDistributedActor.cpp

@@ -14,7 +14,6 @@
 
 #include "CodeSynthesis.h"
 #include "DerivedConformances.h"
-#include "TypeCheckType.h"
 #include "TypeChecker.h"
 #include "swift/AST/ASTMangler.h"
 #include "swift/AST/ASTPrinter.h"
@@ -1066,3 +1065,30 @@ bool CanSynthesizeDistributedActorCodableConformanceRequest::evaluate(
          TypeChecker::conformsToKnownProtocol(
              idTy, KnownProtocolKind::Encodable, actor->getParentModule());
 }
+
+NormalProtocolConformance *
+GetDistributedActorAsActorConformanceRequest::evaluate(
+    Evaluator &evaluator, ProtocolDecl *distributedActorProto) const {
+  auto &ctx = distributedActorProto->getASTContext();
+  auto swiftModule = ctx.getStdlibModule();
+
+  auto actorProto = ctx.getProtocol(KnownProtocolKind::Actor);
+
+  auto ext = findDistributedActorAsActorExtension(
+      distributedActorProto, swiftModule);
+  if (!ext)
+    return nullptr;
+
+  auto genericParam = GenericTypeParamType::get(/*isParameterPack=*/false,
+                                                /*depth=*/0, /*index=*/0, ctx);
+
+  auto distributedActorAsActorConformance = ctx.getNormalConformance(
+      Type(genericParam), actorProto, SourceLoc(), ext,
+      ProtocolConformanceState::Incomplete, /*isUnchecked=*/false,
+      /*isPreconcurrency=*/false);
+  // NOTE: Normally we "register" a conformance, but here we don't
+  // because we cannot (currently) register them in a protocol,
+  // since they do not have conformance tables.
+
+  return distributedActorAsActorConformance;
+}