Convert GetAllErrors() to return an llvm::Error (NFC)

Author: adrian-prantl

lldb/source/Plugins/ExpressionParser/Swift/SwiftExpressionParser.cpp

@@ -1381,8 +1381,7 @@ static llvm::Expected<ParsedExpression> ParseAndImport(
 
   if (expr_diagnostics.HasErrors())
     return make_error<ModuleImportError>(
-        expr_diagnostics.GetAllErrors().AsCString(
-            "Explicit module import error"));
+        llvm::toString(expr_diagnostics.GetAllErrors()));
 
   std::unique_ptr<SwiftASTManipulator> code_manipulator;
   if (repl || !playground) {

lldb/source/Plugins/TypeSystem/Swift/SwiftASTContext.cpp

@@ -937,14 +937,12 @@ bool SwiftASTContext::ScopedDiagnostics::HasErrors() const {
   return false;
 }
 
-Status SwiftASTContext::ScopedDiagnostics::GetAllErrors() const {
+llvm::Error SwiftASTContext::ScopedDiagnostics::GetAllErrors() const {
   // Retrieve the error message from the DiagnosticConsumer.
   DiagnosticManager diagnostic_manager;
   PrintDiagnostics(diagnostic_manager);
-
-  Status error;
-  error.SetErrorString(diagnostic_manager.GetString());
-  return error;
+  return llvm::make_error<llvm::StringError>(diagnostic_manager.GetString(),
+                                             llvm::inconvertibleErrorCode());
 }
 
 SwiftASTContext::ScopedDiagnostics::~ScopedDiagnostics() {

lldb/source/Plugins/TypeSystem/Swift/SwiftASTContext.h

@@ -484,7 +484,7 @@ class SwiftASTContext : public TypeSystemSwift {
     bool HasErrors() const;
     /// Return all errors and warnings that happened during the lifetime of this
     /// object.
-    Status GetAllErrors() const;
+    llvm::Error GetAllErrors() const;
   };
   std::unique_ptr<ScopedDiagnostics> getScopedDiagnosticConsumer();
   /// \}