Tiny improvement of RouteSettings display (#114481)

* impl

* Update packages/flutter/lib/src/widgets/navigator.dart
Co-authored-by: chunhtai <47866232+chunhtai@users.noreply.github.com>

* Update navigator_test.dart
Co-authored-by: chunhtai <47866232+chunhtai@users.noreply.github.com>

packages/flutter/lib/src/widgets/navigator.dart

@@ -548,7 +548,7 @@ class RouteSettings {
   final Object? arguments;
 
   @override
-  String toString() => '${objectRuntimeType(this, 'RouteSettings')}("$name", $arguments)';
+  String toString() => '${objectRuntimeType(this, 'RouteSettings')}(${name == null ? 'none' : '"$name"'}, $arguments)';
 }
 
 /// Describes the configuration of a [Route].

packages/flutter/test/widgets/navigator_test.dart

@@ -3935,6 +3935,16 @@ void main() {
     );
     expect(policy, isA<ReadingOrderTraversalPolicy>());
   });
+
+  group('RouteSettings.toString', () {
+    test('when name is not null, should have double quote', () {
+      expect(const RouteSettings(name: '/home').toString(), 'RouteSettings("/home", null)');
+    });
+
+    test('when name is null, should not have double quote', () {
+      expect(const RouteSettings().toString(), 'RouteSettings(none, null)');
+    });
+  });
 }
 
 typedef AnnouncementCallBack = void Function(Route<dynamic>?);