[Serialization] Use InheritedEntries.getResolvedType to determine type to serialize into interface

Looks like when emitting a module with ` -experimental-skip-all-function-bodies -experimental-skip-non-exportable-decls -experimental-lazy-typecheck`, we don’t run `InheritedTypeRequest`, and thus `inherited.getType()` is `nullptr`. Use `InheritedEntries.getResolvedType` to ensure that `InheritedTypeRequest` gets run to make sure we emit the inherited types into the generated module.

rdar://141440011

Author: ahoppen

lib/Serialization/Serialization.cpp

@@ -4080,9 +4080,11 @@ class Serializer::DeclSerializer : public DeclVisitor<DeclSerializer> {
   /// \returns the number of entries added.
   size_t addInherited(InheritedTypes inheritedEntries,
                       SmallVectorImpl<uint64_t> &result) {
-    for (const auto &inherited : inheritedEntries.getEntries()) {
-      assert(!inherited.getType() || !inherited.getType()->hasArchetype());
-      uint64_t typeRef = S.addTypeRef(inherited.getType());
+    for (size_t i = 0; i < inheritedEntries.size(); ++i) {
+      Type inheritedType = inheritedEntries.getResolvedType(i);
+      const InheritedEntry &inherited = inheritedEntries.getEntry(i);
+      assert(!inheritedType || !inheritedType->hasArchetype());
+      uint64_t typeRef = S.addTypeRef(inheritedType);
       uint64_t originalTypeRef = typeRef;
 
       // Encode options in the low bits;

test/IDE/rdar141440011.swift

@@ -0,0 +1,9 @@
+public protocol MyProto {}
+public struct MyStruct: MyProto {}
+
+// RUN: %empty-directory(%t)
+// RUN: %swift -emit-module -o %t/swift_mod.swiftmodule %s -parse-as-library -experimental-skip-all-function-bodies -experimental-skip-non-exportable-decls -experimental-lazy-typecheck -target arm64-apple-macosx13.0
+// RUN: %target-swift-synthesize-interface -module-name swift_mod -I %t -o - -target arm64-apple-macosx13.0 | %FileCheck %s
+
+
+// CHECK: public struct MyStruct : swift_mod.MyProto