[lldb] Adapt error handling API in ReflectionContext.

Author: adrian-prantl

lldb/source/Plugins/LanguageRuntime/Swift/ReflectionContext.cpp

@@ -180,8 +180,7 @@ class TargetReflectionContext : public ReflectionContextInterface {
     auto *rti =
         m_type_converter.getClassInstanceTypeInfo(&type_ref, *start, provider);
     if (!rti)
-      return llvm::createStringError(
-          "converter returned nullptr typeinfo but no error");
+      return llvm::createStringError(m_type_converter.getLastError());
     return *rti;
   }
 
@@ -201,14 +200,12 @@ class TargetReflectionContext : public ReflectionContextInterface {
                provider ? provider->getId() : 0, ss.str());
     }
 
-    auto type_info = m_reflection_ctx.getTypeInfo(&type_ref, provider);
-    if (!type_info) {
-      std::stringstream ss;
-      ss << "Could not find type info for ";
-      type_ref.dump(ss);
-      ss << " in reflection metadata";
-      return llvm::createStringError(ss.str());
-    }
+    auto type_info = m_reflection_ctx.getTypeInfo(type_ref, provider);
+    if (!type_info)
+      return llvm::joinErrors(
+          llvm::createStringError(
+              "Could not find reflection metadata for type"),
+          type_info.takeError());
 
     if (log && log->GetVerbose()) {
       std::stringstream ss;