diff --git a/pkg/analysis_server/lib/src/services/completion/yaml/pubspec_generator.dart b/pkg/analysis_server/lib/src/services/completion/yaml/pubspec_generator.dart
index 8c01840b..c616d58 100644
--- a/pkg/analysis_server/lib/src/services/completion/yaml/pubspec_generator.dart
+++ b/pkg/analysis_server/lib/src/services/completion/yaml/pubspec_generator.dart
@@ -73,7 +73,6 @@
           }),
         }),
       }),
-      'services': EmptyProducer(), // ListProducer(EmptyProducer()),
       'uses-material-design': BooleanProducer(),
     }),
   });
diff --git a/pkg/front_end/testcases/expression/core_lib_imported.expression.yaml.expect b/pkg/front_end/testcases/expression/core_lib_imported.expression.yaml.expect
index 02ef4d6..5167c83 100644
--- a/pkg/front_end/testcases/expression/core_lib_imported.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/core_lib_imported.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-method /*isNullableByDefault, from org-dartlang-debug:synthetic_debug_expression */ debugExpr() → dynamic
+method /*isLegacy, from org-dartlang-debug:synthetic_debug_expression */ debugExpr() → dynamic
   return dart.core::identical(1, 1);
diff --git a/pkg/front_end/testcases/expression/core_lib_internal.expression.yaml.expect b/pkg/front_end/testcases/expression/core_lib_internal.expression.yaml.expect
index c4ded9a..72b7d9d 100644
--- a/pkg/front_end/testcases/expression/core_lib_internal.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/core_lib_internal.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-method /*isNullableByDefault, from org-dartlang-debug:synthetic_debug_expression */ debugExpr() → dynamic
+method /*isLegacy, from org-dartlang-debug:synthetic_debug_expression */ debugExpr() → dynamic
   return null is dart.collection::Queue<dynamic>*;
diff --git a/pkg/front_end/testcases/expression/from_vm_cc_linked_hash_map.expression.yaml.expect b/pkg/front_end/testcases/expression/from_vm_cc_linked_hash_map.expression.yaml.expect
index 2643d93..15bc127 100644
--- a/pkg/front_end/testcases/expression/from_vm_cc_linked_hash_map.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/from_vm_cc_linked_hash_map.expression.yaml.expect
@@ -1,6 +1,6 @@
 Errors: {
 }
-method /*isNullableByDefault, from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dynamic a, dynamic b) → dynamic
+method /*isLegacy, from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dynamic a, dynamic b) → dynamic
   return ((dynamic a, dynamic b) → dart.core::bool* {
     if(!a._usedData.{dart.core::Object::==}(b._usedData) || !a._deletedKeys.{dart.core::Object::==}(b._deletedKeys) || !a._hashMask.{dart.core::Object::==}(b._hashMask) || !a._index.length.{dart.core::Object::==}(b._index.length) || !a._data.length.{dart.core::Object::==}(b._data.length)) {
       return false;
diff --git a/pkg/front_end/testcases/expression/regress_34224.expression.yaml.expect b/pkg/front_end/testcases/expression/regress_34224.expression.yaml.expect
index 8c2b235..fd35ac2 100644
--- a/pkg/front_end/testcases/expression/regress_34224.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/regress_34224.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-method /*isNullableByDefault, from org-dartlang-debug:synthetic_debug_expression */ debugExpr() → dynamic
+method /*isLegacy, from org-dartlang-debug:synthetic_debug_expression */ debugExpr() → dynamic
   return this.{dart.core::Object::toString}();
diff --git a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.1.expect b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.1.expect
index a789fc9..d40aeb92 100644
--- a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.1.expect
+++ b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.1.expect
@@ -7,7 +7,7 @@
       ;
   }
   abstract class Widget extends fra::Bar implements wid::_HasCreationLocation /*hasConstConstructor*/  {
-    final field wid::_Location? _location /*isNullableByDefault, from null */;
+    final field wid::_Location? _location /*isLegacy, from null */;
     const constructor •({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → fra::Widget
       : super fra::Bar::•(), fra::Widget::_location = $creationLocationd_0dea112b090073317d4
       ;
@@ -45,7 +45,7 @@
       return #C7;
   }
   class Bar extends fra::Widget /*hasConstConstructor*/  {
-    static field dynamic _redirecting# = <dynamic>[foo::Bar::•]/*isNullableByDefault*/;
+    static field dynamic _redirecting# = <dynamic>[foo::Bar::•]/*isLegacy*/;
     const constructor _({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → foo::Bar
       : super fra::Widget::•($creationLocationd_0dea112b090073317d4: $creationLocationd_0dea112b090073317d4)
       ;
@@ -53,7 +53,7 @@
       let dynamic #redirecting_factory = foo::Bar::_ in invalid-expression;
   }
   class Baz extends fra::Widget /*hasConstConstructor*/  {
-    static field dynamic _redirecting# = <dynamic>[foo::Baz::_]/*isNullableByDefault*/;
+    static field dynamic _redirecting# = <dynamic>[foo::Baz::_]/*isLegacy*/;
     const constructor __({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → foo::Baz
       : super fra::Widget::•($creationLocationd_0dea112b090073317d4: $creationLocationd_0dea112b090073317d4)
       ;
diff --git a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.2.expect b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.2.expect
index 489ea3e..ec1cec8 100644
--- a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.2.expect
+++ b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.2.expect
@@ -7,7 +7,7 @@
       ;
   }
   abstract class Widget extends fra::Bar implements wid::_HasCreationLocation /*hasConstConstructor*/  {
-    final field wid::_Location? _location /*isNullableByDefault, from null */;
+    final field wid::_Location? _location /*isLegacy, from null */;
     const constructor •({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → fra::Widget
       : super fra::Bar::•(), fra::Widget::_location = $creationLocationd_0dea112b090073317d4
       ;
@@ -45,7 +45,7 @@
       return #C7;
   }
   class Bar extends fra::Widget /*hasConstConstructor*/  {
-    static field dynamic _redirecting# = <dynamic>[foo::Bar::•]/*isNullableByDefault*/;
+    static field dynamic _redirecting# = <dynamic>[foo::Bar::•]/*isLegacy*/;
     const constructor _({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → foo::Bar
       : super fra::Widget::•($creationLocationd_0dea112b090073317d4: $creationLocationd_0dea112b090073317d4)
       ;
@@ -53,7 +53,7 @@
       let dynamic #redirecting_factory = foo::Bar::_ in invalid-expression;
   }
   class Baz extends fra::Widget /*hasConstConstructor*/  {
-    static field dynamic _redirecting# = <dynamic>[foo::Baz::_]/*isNullableByDefault*/;
+    static field dynamic _redirecting# = <dynamic>[foo::Baz::_]/*isLegacy*/;
     const constructor __({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → foo::Baz
       : super fra::Widget::•($creationLocationd_0dea112b090073317d4: $creationLocationd_0dea112b090073317d4)
       ;
diff --git a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.3.expect b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.3.expect
index a789fc9..d40aeb92 100644
--- a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.3.expect
+++ b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_const.yaml.world.3.expect
@@ -7,7 +7,7 @@
       ;
   }
   abstract class Widget extends fra::Bar implements wid::_HasCreationLocation /*hasConstConstructor*/  {
-    final field wid::_Location? _location /*isNullableByDefault, from null */;
+    final field wid::_Location? _location /*isLegacy, from null */;
     const constructor •({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → fra::Widget
       : super fra::Bar::•(), fra::Widget::_location = $creationLocationd_0dea112b090073317d4
       ;
@@ -45,7 +45,7 @@
       return #C7;
   }
   class Bar extends fra::Widget /*hasConstConstructor*/  {
-    static field dynamic _redirecting# = <dynamic>[foo::Bar::•]/*isNullableByDefault*/;
+    static field dynamic _redirecting# = <dynamic>[foo::Bar::•]/*isLegacy*/;
     const constructor _({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → foo::Bar
       : super fra::Widget::•($creationLocationd_0dea112b090073317d4: $creationLocationd_0dea112b090073317d4)
       ;
@@ -53,7 +53,7 @@
       let dynamic #redirecting_factory = foo::Bar::_ in invalid-expression;
   }
   class Baz extends fra::Widget /*hasConstConstructor*/  {
-    static field dynamic _redirecting# = <dynamic>[foo::Baz::_]/*isNullableByDefault*/;
+    static field dynamic _redirecting# = <dynamic>[foo::Baz::_]/*isLegacy*/;
     const constructor __({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → foo::Baz
       : super fra::Widget::•($creationLocationd_0dea112b090073317d4: $creationLocationd_0dea112b090073317d4)
       ;
diff --git a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_nnbd.yaml.world.1.expect b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_nnbd.yaml.world.1.expect
index aeb8651..c896f26 100644
--- a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_nnbd.yaml.world.1.expect
+++ b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_nnbd.yaml.world.1.expect
@@ -7,7 +7,7 @@
       ;
   }
   abstract class Widget extends fra::Bar implements wid::_HasCreationLocation /*hasConstConstructor*/  {
-    final field wid::_Location? _location /*isNullableByDefault, from null */;
+    final field wid::_Location? _location /*isLegacy, from null */;
     const constructor •({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → fra::Widget
       : super fra::Bar::•(), fra::Widget::_location = $creationLocationd_0dea112b090073317d4
       ;
diff --git a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_nnbd.yaml.world.2.expect b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_nnbd.yaml.world.2.expect
index 871b5ac..23d9796 100644
--- a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_nnbd.yaml.world.2.expect
+++ b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transform_nnbd.yaml.world.2.expect
@@ -7,7 +7,7 @@
       ;
   }
   abstract class Widget extends fra::Bar implements wid::_HasCreationLocation /*hasConstConstructor*/  {
-    final field wid::_Location? _location /*isNullableByDefault, from null */;
+    final field wid::_Location? _location /*isLegacy, from null */;
     const constructor •({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → fra::Widget
       : super fra::Bar::•(), fra::Widget::_location = $creationLocationd_0dea112b090073317d4
       ;
diff --git a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_43371.yaml.world.1.expect b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_43371.yaml.world.1.expect
index fc776ae..b666fa7 100644
--- a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_43371.yaml.world.1.expect
+++ b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_43371.yaml.world.1.expect
@@ -8,7 +8,7 @@
   }
   abstract class Widget extends fra::Bar implements wid::_HasCreationLocation /*hasConstConstructor*/  {
     final field dart.core::Object? key;
-    final field wid::_Location? _location /*isNullableByDefault, from null */;
+    final field wid::_Location? _location /*isLegacy, from null */;
     const constructor •({dart.core::Object? key = #C1, wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → fra::Widget
       : fra::Widget::key = key, super fra::Bar::•(), fra::Widget::_location = $creationLocationd_0dea112b090073317d4
       ;
diff --git a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_43371.yaml.world.2.expect b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_43371.yaml.world.2.expect
index 6a2fb38..6d4e387 100644
--- a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_43371.yaml.world.2.expect
+++ b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_43371.yaml.world.2.expect
@@ -8,7 +8,7 @@
   }
   abstract class Widget extends fra::Bar implements wid::_HasCreationLocation /*hasConstConstructor*/  {
     final field dart.core::Object? key;
-    final field wid::_Location? _location /*isNullableByDefault, from null */;
+    final field wid::_Location? _location /*isLegacy, from null */;
     const constructor •({dart.core::Object? key = #C1, wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → fra::Widget
       : fra::Widget::key = key, super fra::Bar::•(), fra::Widget::_location = $creationLocationd_0dea112b090073317d4
       ;
diff --git a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_non_const.yaml.world.1.expect b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_non_const.yaml.world.1.expect
index 89e94d3..506067f 100644
--- a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_non_const.yaml.world.1.expect
+++ b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_non_const.yaml.world.1.expect
@@ -7,7 +7,7 @@
       ;
   }
   abstract class Widget extends fra::Bar implements wid::_HasCreationLocation /*hasConstConstructor*/  {
-    final field wid::_Location? _location /*isNullableByDefault, from null */;
+    final field wid::_Location? _location /*isLegacy, from null */;
     const constructor •({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → fra::Widget
       : super fra::Bar::•(), fra::Widget::_location = $creationLocationd_0dea112b090073317d4
       ;
diff --git a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_non_const.yaml.world.2.expect b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_non_const.yaml.world.2.expect
index a33902f..fda5bb6 100644
--- a/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_non_const.yaml.world.2.expect
+++ b/pkg/front_end/testcases/incremental_initialize_from_dill/flutter_widget_transformer_non_const.yaml.world.2.expect
@@ -7,7 +7,7 @@
       ;
   }
   abstract class Widget extends fra::Bar implements wid::_HasCreationLocation /*hasConstConstructor*/  {
-    final field wid::_Location? _location /*isNullableByDefault, from null */;
+    final field wid::_Location? _location /*isLegacy, from null */;
     const constructor •({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → fra::Widget
       : super fra::Bar::•(), fra::Widget::_location = $creationLocationd_0dea112b090073317d4
       ;
diff --git a/pkg/front_end/testcases/incremental_initialize_from_dill/no_outline_change_44_flutter.yaml.world.1.expect b/pkg/front_end/testcases/incremental_initialize_from_dill/no_outline_change_44_flutter.yaml.world.1.expect
index 0279835..1c83cc5 100644
--- a/pkg/front_end/testcases/incremental_initialize_from_dill/no_outline_change_44_flutter.yaml.world.1.expect
+++ b/pkg/front_end/testcases/incremental_initialize_from_dill/no_outline_change_44_flutter.yaml.world.1.expect
@@ -4,7 +4,7 @@
   import "package:flutter/src/widgets/widget_inspector.dart";
 
   abstract class Widget extends dart.core::Object implements wid::_HasCreationLocation {
-    final field wid::_Location? _location /*isNullableByDefault, from null */;
+    final field wid::_Location? _location /*isLegacy, from null */;
     synthetic constructor •({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → fra::Widget
       : super dart.core::Object::•(), fra::Widget::_location = $creationLocationd_0dea112b090073317d4
       ;
diff --git a/pkg/front_end/testcases/incremental_initialize_from_dill/no_outline_change_44_flutter.yaml.world.2.expect b/pkg/front_end/testcases/incremental_initialize_from_dill/no_outline_change_44_flutter.yaml.world.2.expect
index 0279835..1c83cc5 100644
--- a/pkg/front_end/testcases/incremental_initialize_from_dill/no_outline_change_44_flutter.yaml.world.2.expect
+++ b/pkg/front_end/testcases/incremental_initialize_from_dill/no_outline_change_44_flutter.yaml.world.2.expect
@@ -4,7 +4,7 @@
   import "package:flutter/src/widgets/widget_inspector.dart";
 
   abstract class Widget extends dart.core::Object implements wid::_HasCreationLocation {
-    final field wid::_Location? _location /*isNullableByDefault, from null */;
+    final field wid::_Location? _location /*isLegacy, from null */;
     synthetic constructor •({wid::_Location? $creationLocationd_0dea112b090073317d4 = #C1}) → fra::Widget
       : super dart.core::Object::•(), fra::Widget::_location = $creationLocationd_0dea112b090073317d4
       ;
diff --git a/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.outline.expect b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.outline.expect
index bed220f..efac096 100644
--- a/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.outline.expect
+++ b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.outline.expect
@@ -19,7 +19,7 @@
 export "org-dartlang-testcase:///ambiguous_main_export_lib1.dart";
 export "org-dartlang-testcase:///ambiguous_main_export_lib2.dart";
 
-static const field dynamic _exports# = "{\"main\":\"'main' is exported from both 'pkg/front_end/testcases/nnbd/ambiguous_main_export_lib1.dart' and 'pkg/front_end/testcases/nnbd/ambiguous_main_export_lib2.dart'.\"}" /*isNullableByDefault, from null */;
+static const field dynamic _exports# = "{\"main\":\"'main' is exported from both 'pkg/front_end/testcases/nnbd/ambiguous_main_export_lib1.dart' and 'pkg/front_end/testcases/nnbd/ambiguous_main_export_lib2.dart'.\"}" /*isLegacy, from null */;
 
 library /*isNonNullableByDefault*/;
 import self as self3;
diff --git a/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.strong.expect b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.strong.expect
index 8a5ab57..54558c4 100644
--- a/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.strong.expect
+++ b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.strong.expect
@@ -19,7 +19,7 @@
 export "org-dartlang-testcase:///ambiguous_main_export_lib1.dart";
 export "org-dartlang-testcase:///ambiguous_main_export_lib2.dart";
 
-static const field dynamic _exports# = #C1 /*isNullableByDefault, from null */;
+static const field dynamic _exports# = #C1 /*isLegacy, from null */;
 
 library /*isNonNullableByDefault*/;
 import self as self3;
diff --git a/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.strong.transformed.expect b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.strong.transformed.expect
index 8a5ab57..54558c4 100644
--- a/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.strong.transformed.expect
@@ -19,7 +19,7 @@
 export "org-dartlang-testcase:///ambiguous_main_export_lib1.dart";
 export "org-dartlang-testcase:///ambiguous_main_export_lib2.dart";
 
-static const field dynamic _exports# = #C1 /*isNullableByDefault, from null */;
+static const field dynamic _exports# = #C1 /*isLegacy, from null */;
 
 library /*isNonNullableByDefault*/;
 import self as self3;
diff --git a/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.weak.expect b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.weak.expect
index 8a5ab57..54558c4 100644
--- a/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.weak.expect
@@ -19,7 +19,7 @@
 export "org-dartlang-testcase:///ambiguous_main_export_lib1.dart";
 export "org-dartlang-testcase:///ambiguous_main_export_lib2.dart";
 
-static const field dynamic _exports# = #C1 /*isNullableByDefault, from null */;
+static const field dynamic _exports# = #C1 /*isLegacy, from null */;
 
 library /*isNonNullableByDefault*/;
 import self as self3;
diff --git a/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.weak.transformed.expect
index 8a5ab57..54558c4 100644
--- a/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/ambiguous_main_export.dart.weak.transformed.expect
@@ -19,7 +19,7 @@
 export "org-dartlang-testcase:///ambiguous_main_export_lib1.dart";
 export "org-dartlang-testcase:///ambiguous_main_export_lib2.dart";
 
-static const field dynamic _exports# = #C1 /*isNullableByDefault, from null */;
+static const field dynamic _exports# = #C1 /*isLegacy, from null */;
 
 library /*isNonNullableByDefault*/;
 import self as self3;
diff --git a/pkg/front_end/testcases/nnbd/issue42362.dart.outline.expect b/pkg/front_end/testcases/nnbd/issue42362.dart.outline.expect
index 8b438e7..36632a1 100644
--- a/pkg/front_end/testcases/nnbd/issue42362.dart.outline.expect
+++ b/pkg/front_end/testcases/nnbd/issue42362.dart.outline.expect
@@ -71,7 +71,7 @@
 
 class A extends core::Object {
   final field core::int i;
-  static field dynamic _redirecting# = <dynamic>[self::A::factory3, self::A::factory4, self::A::factory5, self::A::factory6, self::A::factory7]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::A::factory3, self::A::factory4, self::A::factory5, self::A::factory6, self::A::factory7]/*isLegacy*/;
   constructor constructor1([core::int i]) → self::A
     ;
   constructor constructor2({core::int i}) → self::A
@@ -129,7 +129,7 @@
 }
 class C extends core::Object implements self::B {
   field core::int i;
-  static field dynamic _redirecting# = <dynamic>[self::C::factory3, self::C::factory4, self::C::factory5, self::C::factory6, self::C::factory7]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::factory3, self::C::factory4, self::C::factory5, self::C::factory6, self::C::factory7]/*isLegacy*/;
   constructor constructor1([core::int i]) → self::C
     ;
   constructor constructor2({core::int i}) → self::C
diff --git a/pkg/front_end/testcases/nnbd/issue42362.dart.strong.expect b/pkg/front_end/testcases/nnbd/issue42362.dart.strong.expect
index 62f2fb2..0f40eb2 100644
--- a/pkg/front_end/testcases/nnbd/issue42362.dart.strong.expect
+++ b/pkg/front_end/testcases/nnbd/issue42362.dart.strong.expect
@@ -87,7 +87,7 @@
 
 class A extends core::Object {
   final field core::int i;
-  static field dynamic _redirecting# = <dynamic>[self::A::factory3, self::A::factory4, self::A::factory5, self::A::factory6, self::A::factory7]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::A::factory3, self::A::factory4, self::A::factory5, self::A::factory6, self::A::factory7]/*isLegacy*/;
   constructor constructor1([core::int i = #C1]) → self::A
     : self::A::i = i, super core::Object::•()
     ;
@@ -154,7 +154,7 @@
 }
 class C extends core::Object implements self::B {
   field core::int i;
-  static field dynamic _redirecting# = <dynamic>[self::C::factory3, self::C::factory4, self::C::factory5, self::C::factory6, self::C::factory7]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::factory3, self::C::factory4, self::C::factory5, self::C::factory6, self::C::factory7]/*isLegacy*/;
   constructor constructor1([core::int i = #C1]) → self::C
     : self::C::i = i, super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd/issue42362.dart.strong.transformed.expect b/pkg/front_end/testcases/nnbd/issue42362.dart.strong.transformed.expect
index a58e129..2d7d920 100644
--- a/pkg/front_end/testcases/nnbd/issue42362.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue42362.dart.strong.transformed.expect
@@ -87,7 +87,7 @@
 
 class A extends core::Object {
   final field core::int i;
-  static field dynamic _redirecting# = <dynamic>[self::A::factory3, self::A::factory4, self::A::factory5, self::A::factory6, self::A::factory7]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::A::factory3, self::A::factory4, self::A::factory5, self::A::factory6, self::A::factory7]/*isLegacy*/;
   constructor constructor1([core::int i = #C1]) → self::A
     : self::A::i = i, super core::Object::•()
     ;
@@ -154,7 +154,7 @@
 }
 class C extends core::Object implements self::B {
   field core::int i;
-  static field dynamic _redirecting# = <dynamic>[self::C::factory3, self::C::factory4, self::C::factory5, self::C::factory6, self::C::factory7]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::factory3, self::C::factory4, self::C::factory5, self::C::factory6, self::C::factory7]/*isLegacy*/;
   constructor constructor1([core::int i = #C1]) → self::C
     : self::C::i = i, super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd/issue42362.dart.weak.expect b/pkg/front_end/testcases/nnbd/issue42362.dart.weak.expect
index 62f2fb2..0f40eb2 100644
--- a/pkg/front_end/testcases/nnbd/issue42362.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd/issue42362.dart.weak.expect
@@ -87,7 +87,7 @@
 
 class A extends core::Object {
   final field core::int i;
-  static field dynamic _redirecting# = <dynamic>[self::A::factory3, self::A::factory4, self::A::factory5, self::A::factory6, self::A::factory7]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::A::factory3, self::A::factory4, self::A::factory5, self::A::factory6, self::A::factory7]/*isLegacy*/;
   constructor constructor1([core::int i = #C1]) → self::A
     : self::A::i = i, super core::Object::•()
     ;
@@ -154,7 +154,7 @@
 }
 class C extends core::Object implements self::B {
   field core::int i;
-  static field dynamic _redirecting# = <dynamic>[self::C::factory3, self::C::factory4, self::C::factory5, self::C::factory6, self::C::factory7]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::factory3, self::C::factory4, self::C::factory5, self::C::factory6, self::C::factory7]/*isLegacy*/;
   constructor constructor1([core::int i = #C1]) → self::C
     : self::C::i = i, super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd/issue42362.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue42362.dart.weak.transformed.expect
index 33d6b11..253c393 100644
--- a/pkg/front_end/testcases/nnbd/issue42362.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue42362.dart.weak.transformed.expect
@@ -87,7 +87,7 @@
 
 class A extends core::Object {
   final field core::int i;
-  static field dynamic _redirecting# = <dynamic>[self::A::factory3, self::A::factory4, self::A::factory5, self::A::factory6, self::A::factory7]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::A::factory3, self::A::factory4, self::A::factory5, self::A::factory6, self::A::factory7]/*isLegacy*/;
   constructor constructor1([core::int i = #C1]) → self::A
     : self::A::i = i, super core::Object::•()
     ;
@@ -154,7 +154,7 @@
 }
 class C extends core::Object implements self::B {
   field core::int i;
-  static field dynamic _redirecting# = <dynamic>[self::C::factory3, self::C::factory4, self::C::factory5, self::C::factory6, self::C::factory7]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::factory3, self::C::factory4, self::C::factory5, self::C::factory6, self::C::factory7]/*isLegacy*/;
   constructor constructor1([core::int i = #C1]) → self::C
     : self::C::i = i, super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd/issue42844_1.dart.outline.expect b/pkg/front_end/testcases/nnbd/issue42844_1.dart.outline.expect
index a52904f..1b6e3c7 100644
--- a/pkg/front_end/testcases/nnbd/issue42844_1.dart.outline.expect
+++ b/pkg/front_end/testcases/nnbd/issue42844_1.dart.outline.expect
@@ -4,7 +4,7 @@
 
 class C extends core::Object {
   field Never n;
-  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isLegacy*/;
   static factory •(Never n) → self::C
     let dynamic #redirecting_factory = self::D::• in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue42844_1.dart.strong.expect b/pkg/front_end/testcases/nnbd/issue42844_1.dart.strong.expect
index 9f1d04c..579f1e9 100644
--- a/pkg/front_end/testcases/nnbd/issue42844_1.dart.strong.expect
+++ b/pkg/front_end/testcases/nnbd/issue42844_1.dart.strong.expect
@@ -11,7 +11,7 @@
 
 class C extends core::Object {
   field Never n = null;
-  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isLegacy*/;
   static factory •(Never n) → self::C
     let dynamic #redirecting_factory = self::D::• in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue42844_1.dart.strong.transformed.expect b/pkg/front_end/testcases/nnbd/issue42844_1.dart.strong.transformed.expect
index 7a9d7ad..9bf278b 100644
--- a/pkg/front_end/testcases/nnbd/issue42844_1.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue42844_1.dart.strong.transformed.expect
@@ -11,7 +11,7 @@
 
 class C extends core::Object {
   field Never n = null;
-  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isLegacy*/;
   static factory •(Never n) → self::C
     let<BottomType> #redirecting_factory = self::D::• in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue42844_1.dart.weak.expect b/pkg/front_end/testcases/nnbd/issue42844_1.dart.weak.expect
index 9f1d04c..579f1e9 100644
--- a/pkg/front_end/testcases/nnbd/issue42844_1.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd/issue42844_1.dart.weak.expect
@@ -11,7 +11,7 @@
 
 class C extends core::Object {
   field Never n = null;
-  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isLegacy*/;
   static factory •(Never n) → self::C
     let dynamic #redirecting_factory = self::D::• in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue42844_1.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue42844_1.dart.weak.transformed.expect
index 7a9d7ad..9bf278b 100644
--- a/pkg/front_end/testcases/nnbd/issue42844_1.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue42844_1.dart.weak.transformed.expect
@@ -11,7 +11,7 @@
 
 class C extends core::Object {
   field Never n = null;
-  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isLegacy*/;
   static factory •(Never n) → self::C
     let<BottomType> #redirecting_factory = self::D::• in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue42844_2.dart.outline.expect b/pkg/front_end/testcases/nnbd/issue42844_2.dart.outline.expect
index 40df7c4..b211f2f 100644
--- a/pkg/front_end/testcases/nnbd/issue42844_2.dart.outline.expect
+++ b/pkg/front_end/testcases/nnbd/issue42844_2.dart.outline.expect
@@ -4,7 +4,7 @@
 
 class C extends core::Object {
   final field dynamic n;
-  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isLegacy*/;
   static factory •(dynamic n) → self::C
     let dynamic #redirecting_factory = self::D::• in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue42844_2.dart.strong.expect b/pkg/front_end/testcases/nnbd/issue42844_2.dart.strong.expect
index afaa082..1a0f908 100644
--- a/pkg/front_end/testcases/nnbd/issue42844_2.dart.strong.expect
+++ b/pkg/front_end/testcases/nnbd/issue42844_2.dart.strong.expect
@@ -12,7 +12,7 @@
 
 class C extends core::Object {
   final field dynamic n = null;
-  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isLegacy*/;
   static factory •(dynamic n) → self::C
     let dynamic #redirecting_factory = self::D::• in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue42844_2.dart.strong.transformed.expect b/pkg/front_end/testcases/nnbd/issue42844_2.dart.strong.transformed.expect
index 4e1efe4..ba70d21 100644
--- a/pkg/front_end/testcases/nnbd/issue42844_2.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue42844_2.dart.strong.transformed.expect
@@ -12,7 +12,7 @@
 
 class C extends core::Object {
   final field dynamic n = null;
-  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isLegacy*/;
   static factory •(dynamic n) → self::C
     let<BottomType> #redirecting_factory = self::D::• in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue42844_2.dart.weak.expect b/pkg/front_end/testcases/nnbd/issue42844_2.dart.weak.expect
index afaa082..1a0f908 100644
--- a/pkg/front_end/testcases/nnbd/issue42844_2.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd/issue42844_2.dart.weak.expect
@@ -12,7 +12,7 @@
 
 class C extends core::Object {
   final field dynamic n = null;
-  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isLegacy*/;
   static factory •(dynamic n) → self::C
     let dynamic #redirecting_factory = self::D::• in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue42844_2.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue42844_2.dart.weak.transformed.expect
index 4e1efe4..ba70d21 100644
--- a/pkg/front_end/testcases/nnbd/issue42844_2.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue42844_2.dart.weak.transformed.expect
@@ -12,7 +12,7 @@
 
 class C extends core::Object {
   final field dynamic n = null;
-  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::•]/*isLegacy*/;
   static factory •(dynamic n) → self::C
     let<BottomType> #redirecting_factory = self::D::• in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue43211.dart.outline.expect b/pkg/front_end/testcases/nnbd/issue43211.dart.outline.expect
index 2ff42f4..1a53ad9 100644
--- a/pkg/front_end/testcases/nnbd/issue43211.dart.outline.expect
+++ b/pkg/front_end/testcases/nnbd/issue43211.dart.outline.expect
@@ -121,7 +121,7 @@
     ;
 }
 class C extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isLegacy*/;
   constructor internal(dynamic _) → self::C
     ;
   static factory redirect(self::A<self::A<Null>>? a) → self::C
diff --git a/pkg/front_end/testcases/nnbd/issue43211.dart.strong.expect b/pkg/front_end/testcases/nnbd/issue43211.dart.strong.expect
index 54f0536..5c0c199 100644
--- a/pkg/front_end/testcases/nnbd/issue43211.dart.strong.expect
+++ b/pkg/front_end/testcases/nnbd/issue43211.dart.strong.expect
@@ -221,7 +221,7 @@
   }
 }
 class C extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isLegacy*/;
   constructor internal(dynamic _) → self::C
     : super core::Object::•() {
     self::A<self::A<Null>>? a;
diff --git a/pkg/front_end/testcases/nnbd/issue43211.dart.strong.transformed.expect b/pkg/front_end/testcases/nnbd/issue43211.dart.strong.transformed.expect
index e77cc1a..07265e4 100644
--- a/pkg/front_end/testcases/nnbd/issue43211.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue43211.dart.strong.transformed.expect
@@ -221,7 +221,7 @@
   }
 }
 class C extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isLegacy*/;
   constructor internal(dynamic _) → self::C
     : super core::Object::•() {
     self::A<self::A<Null>>? a;
diff --git a/pkg/front_end/testcases/nnbd/issue43211.dart.weak.expect b/pkg/front_end/testcases/nnbd/issue43211.dart.weak.expect
index 54f0536..5c0c199 100644
--- a/pkg/front_end/testcases/nnbd/issue43211.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd/issue43211.dart.weak.expect
@@ -221,7 +221,7 @@
   }
 }
 class C extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isLegacy*/;
   constructor internal(dynamic _) → self::C
     : super core::Object::•() {
     self::A<self::A<Null>>? a;
diff --git a/pkg/front_end/testcases/nnbd/issue43211.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue43211.dart.weak.transformed.expect
index e77cc1a..07265e4 100644
--- a/pkg/front_end/testcases/nnbd/issue43211.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue43211.dart.weak.transformed.expect
@@ -221,7 +221,7 @@
   }
 }
 class C extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isLegacy*/;
   constructor internal(dynamic _) → self::C
     : super core::Object::•() {
     self::A<self::A<Null>>? a;
diff --git a/pkg/front_end/testcases/nnbd/issue43276.dart.outline.expect b/pkg/front_end/testcases/nnbd/issue43276.dart.outline.expect
index 46f5c3e..9cbb91e 100644
--- a/pkg/front_end/testcases/nnbd/issue43276.dart.outline.expect
+++ b/pkg/front_end/testcases/nnbd/issue43276.dart.outline.expect
@@ -14,7 +14,7 @@
 import "dart:core" as core;
 
 class C extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isLegacy*/;
   constructor gen({core::int i}) → self::C
     ;
   static factory fact({core::int i}) → self::C
diff --git a/pkg/front_end/testcases/nnbd/issue43276.dart.strong.expect b/pkg/front_end/testcases/nnbd/issue43276.dart.strong.expect
index a827c7e..dfcedf7 100644
--- a/pkg/front_end/testcases/nnbd/issue43276.dart.strong.expect
+++ b/pkg/front_end/testcases/nnbd/issue43276.dart.strong.expect
@@ -14,7 +14,7 @@
 import "dart:core" as core;
 
 class C extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isLegacy*/;
   constructor gen({core::int i = #C1}) → self::C
     : super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd/issue43276.dart.strong.transformed.expect b/pkg/front_end/testcases/nnbd/issue43276.dart.strong.transformed.expect
index 3a35612..ac206c0 100644
--- a/pkg/front_end/testcases/nnbd/issue43276.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue43276.dart.strong.transformed.expect
@@ -14,7 +14,7 @@
 import "dart:core" as core;
 
 class C extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isLegacy*/;
   constructor gen({core::int i = #C1}) → self::C
     : super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd/issue43276.dart.weak.expect b/pkg/front_end/testcases/nnbd/issue43276.dart.weak.expect
index a827c7e..dfcedf7 100644
--- a/pkg/front_end/testcases/nnbd/issue43276.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd/issue43276.dart.weak.expect
@@ -14,7 +14,7 @@
 import "dart:core" as core;
 
 class C extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isLegacy*/;
   constructor gen({core::int i = #C1}) → self::C
     : super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd/issue43276.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue43276.dart.weak.transformed.expect
index 3a35612..ac206c0 100644
--- a/pkg/front_end/testcases/nnbd/issue43276.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue43276.dart.weak.transformed.expect
@@ -14,7 +14,7 @@
 import "dart:core" as core;
 
 class C extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C::redirect]/*isLegacy*/;
   constructor gen({core::int i = #C1}) → self::C
     : super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd/issue43918.dart.outline.expect b/pkg/front_end/testcases/nnbd/issue43918.dart.outline.expect
index 2e633c9..9bff7b0 100644
--- a/pkg/front_end/testcases/nnbd/issue43918.dart.outline.expect
+++ b/pkg/front_end/testcases/nnbd/issue43918.dart.outline.expect
@@ -3,7 +3,7 @@
 import "dart:core" as core;
 
 abstract class A<T extends core::Object? = dynamic> extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::A::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::A::•]/*isLegacy*/;
   static factory •<T extends core::Object? = dynamic>(self::A::•::T% value) → self::A<self::A::•::T%>
     let dynamic #redirecting_factory = self::_A::• in let self::A::•::T% #typeArg0 = null in invalid-expression;
 }
@@ -12,7 +12,7 @@
     ;
 }
 abstract class B<T extends core::Object? = dynamic> extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::B::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::B::•]/*isLegacy*/;
   static factory •<T extends core::Object? = dynamic>(core::int value) → self::B<self::B::•::T%>
     let dynamic #redirecting_factory = self::_B::• in let self::B::•::T% #typeArg0 = null in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue43918.dart.strong.expect b/pkg/front_end/testcases/nnbd/issue43918.dart.strong.expect
index 1d6771b..33ae9c2 100644
--- a/pkg/front_end/testcases/nnbd/issue43918.dart.strong.expect
+++ b/pkg/front_end/testcases/nnbd/issue43918.dart.strong.expect
@@ -3,7 +3,7 @@
 import "dart:core" as core;
 
 abstract class A<T extends core::Object? = dynamic> extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::A::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::A::•]/*isLegacy*/;
   static factory •<T extends core::Object? = dynamic>(self::A::•::T% value) → self::A<self::A::•::T%>
     let dynamic #redirecting_factory = self::_A::• in let self::A::•::T% #typeArg0 = null in invalid-expression;
 }
@@ -13,7 +13,7 @@
     ;
 }
 abstract class B<T extends core::Object? = dynamic> extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::B::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::B::•]/*isLegacy*/;
   static factory •<T extends core::Object? = dynamic>(core::int value) → self::B<self::B::•::T%>
     let dynamic #redirecting_factory = self::_B::• in let self::B::•::T% #typeArg0 = null in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue43918.dart.strong.transformed.expect b/pkg/front_end/testcases/nnbd/issue43918.dart.strong.transformed.expect
index 143829a..1669379 100644
--- a/pkg/front_end/testcases/nnbd/issue43918.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue43918.dart.strong.transformed.expect
@@ -3,7 +3,7 @@
 import "dart:core" as core;
 
 abstract class A<T extends core::Object? = dynamic> extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::A::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::A::•]/*isLegacy*/;
   static factory •<T extends core::Object? = dynamic>(self::A::•::T% value) → self::A<self::A::•::T%>
     let<BottomType> #redirecting_factory = self::_A::• in let self::A::•::T% #typeArg0 = null in invalid-expression;
 }
@@ -13,7 +13,7 @@
     ;
 }
 abstract class B<T extends core::Object? = dynamic> extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::B::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::B::•]/*isLegacy*/;
   static factory •<T extends core::Object? = dynamic>(core::int value) → self::B<self::B::•::T%>
     let<BottomType> #redirecting_factory = self::_B::• in let self::B::•::T% #typeArg0 = null in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue43918.dart.weak.expect b/pkg/front_end/testcases/nnbd/issue43918.dart.weak.expect
index 1d6771b..33ae9c2 100644
--- a/pkg/front_end/testcases/nnbd/issue43918.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd/issue43918.dart.weak.expect
@@ -3,7 +3,7 @@
 import "dart:core" as core;
 
 abstract class A<T extends core::Object? = dynamic> extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::A::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::A::•]/*isLegacy*/;
   static factory •<T extends core::Object? = dynamic>(self::A::•::T% value) → self::A<self::A::•::T%>
     let dynamic #redirecting_factory = self::_A::• in let self::A::•::T% #typeArg0 = null in invalid-expression;
 }
@@ -13,7 +13,7 @@
     ;
 }
 abstract class B<T extends core::Object? = dynamic> extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::B::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::B::•]/*isLegacy*/;
   static factory •<T extends core::Object? = dynamic>(core::int value) → self::B<self::B::•::T%>
     let dynamic #redirecting_factory = self::_B::• in let self::B::•::T% #typeArg0 = null in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/issue43918.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/issue43918.dart.weak.transformed.expect
index 143829a..1669379 100644
--- a/pkg/front_end/testcases/nnbd/issue43918.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/issue43918.dart.weak.transformed.expect
@@ -3,7 +3,7 @@
 import "dart:core" as core;
 
 abstract class A<T extends core::Object? = dynamic> extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::A::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::A::•]/*isLegacy*/;
   static factory •<T extends core::Object? = dynamic>(self::A::•::T% value) → self::A<self::A::•::T%>
     let<BottomType> #redirecting_factory = self::_A::• in let self::A::•::T% #typeArg0 = null in invalid-expression;
 }
@@ -13,7 +13,7 @@
     ;
 }
 abstract class B<T extends core::Object? = dynamic> extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::B::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::B::•]/*isLegacy*/;
   static factory •<T extends core::Object? = dynamic>(core::int value) → self::B<self::B::•::T%>
     let<BottomType> #redirecting_factory = self::_B::• in let self::B::•::T% #typeArg0 = null in invalid-expression;
 }
diff --git a/pkg/front_end/testcases/nnbd/override_checks.dart.outline.expect b/pkg/front_end/testcases/nnbd/override_checks.dart.outline.expect
index 45009c6..a3f0156 100644
--- a/pkg/front_end/testcases/nnbd/override_checks.dart.outline.expect
+++ b/pkg/front_end/testcases/nnbd/override_checks.dart.outline.expect
@@ -62,7 +62,7 @@
     ;
 }
 class C1 extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C1::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C1::•]/*isLegacy*/;
   static factory •() → self::C1
     let dynamic #redirecting_factory = self::C2::• in let core::int? #typeArg0 = null in invalid-expression;
 }
@@ -71,7 +71,7 @@
     ;
 }
 class D extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::D::bar]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::D::bar]/*isLegacy*/;
   constructor foo(core::num x) → self::D
     ;
   static factory bar(core::num? x) → self::D
diff --git a/pkg/front_end/testcases/nnbd/override_checks.dart.strong.expect b/pkg/front_end/testcases/nnbd/override_checks.dart.strong.expect
index 4b9d35a..5ca1bf7 100644
--- a/pkg/front_end/testcases/nnbd/override_checks.dart.strong.expect
+++ b/pkg/front_end/testcases/nnbd/override_checks.dart.strong.expect
@@ -62,7 +62,7 @@
   method hest(core::num value) → void {}
 }
 class C1 extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C1::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C1::•]/*isLegacy*/;
   static factory •() → self::C1
     let dynamic #redirecting_factory = self::C2::• in let core::int? #typeArg0 = null in invalid-expression;
 }
@@ -72,7 +72,7 @@
     ;
 }
 class D extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::D::bar]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::D::bar]/*isLegacy*/;
   constructor foo(core::num x) → self::D
     : super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd/override_checks.dart.strong.transformed.expect b/pkg/front_end/testcases/nnbd/override_checks.dart.strong.transformed.expect
index eb84971..de6bd24 100644
--- a/pkg/front_end/testcases/nnbd/override_checks.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/override_checks.dart.strong.transformed.expect
@@ -62,7 +62,7 @@
   method hest(core::num value) → void {}
 }
 class C1 extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C1::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C1::•]/*isLegacy*/;
   static factory •() → self::C1
     let<BottomType> #redirecting_factory = self::C2::• in let core::int? #typeArg0 = null in invalid-expression;
 }
@@ -72,7 +72,7 @@
     ;
 }
 class D extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::D::bar]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::D::bar]/*isLegacy*/;
   constructor foo(core::num x) → self::D
     : super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd/override_checks.dart.weak.expect b/pkg/front_end/testcases/nnbd/override_checks.dart.weak.expect
index 4b9d35a..5ca1bf7 100644
--- a/pkg/front_end/testcases/nnbd/override_checks.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd/override_checks.dart.weak.expect
@@ -62,7 +62,7 @@
   method hest(core::num value) → void {}
 }
 class C1 extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C1::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C1::•]/*isLegacy*/;
   static factory •() → self::C1
     let dynamic #redirecting_factory = self::C2::• in let core::int? #typeArg0 = null in invalid-expression;
 }
@@ -72,7 +72,7 @@
     ;
 }
 class D extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::D::bar]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::D::bar]/*isLegacy*/;
   constructor foo(core::num x) → self::D
     : super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd/override_checks.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd/override_checks.dart.weak.transformed.expect
index eb84971..de6bd24 100644
--- a/pkg/front_end/testcases/nnbd/override_checks.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd/override_checks.dart.weak.transformed.expect
@@ -62,7 +62,7 @@
   method hest(core::num value) → void {}
 }
 class C1 extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::C1::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::C1::•]/*isLegacy*/;
   static factory •() → self::C1
     let<BottomType> #redirecting_factory = self::C2::• in let core::int? #typeArg0 = null in invalid-expression;
 }
@@ -72,7 +72,7 @@
     ;
 }
 class D extends core::Object {
-  static field dynamic _redirecting# = <dynamic>[self::D::bar]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[self::D::bar]/*isLegacy*/;
   constructor foo(core::num x) → self::D
     : super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd_mixed/flutter_issue_63029/flutter_issue_63029.dart.weak.expect b/pkg/front_end/testcases/nnbd_mixed/flutter_issue_63029/flutter_issue_63029.dart.weak.expect
index ed414cf..91bdcec 100644
--- a/pkg/front_end/testcases/nnbd_mixed/flutter_issue_63029/flutter_issue_63029.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/flutter_issue_63029/flutter_issue_63029.dart.weak.expect
@@ -16,7 +16,7 @@
   synthetic constructor •() → self::_F&B&D
     : super flu::B::•()
     ;
-  abstract member-signature operator /*isNullableByDefault*/ ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
 }
 class F extends self::_F&B&D {
   synthetic constructor •() → self::F
diff --git a/pkg/front_end/testcases/nnbd_mixed/flutter_issue_63029/flutter_issue_63029.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/flutter_issue_63029/flutter_issue_63029.dart.weak.transformed.expect
index 465aafd..fef3899 100644
--- a/pkg/front_end/testcases/nnbd_mixed/flutter_issue_63029/flutter_issue_63029.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/flutter_issue_63029/flutter_issue_63029.dart.weak.transformed.expect
@@ -16,16 +16,16 @@
   synthetic constructor •() → self::_F&B&D
     : super flu::B::•()
     ;
-  abstract member-signature operator /*isNullableByDefault, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ ==(dynamic other) → core::bool*; -> core::Object::==
-  abstract member-signature get /*isNullableByDefault, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ _identityHashCode() → core::int*; -> core::Object::_identityHashCode
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
-  abstract member-signature get /*isNullableByDefault, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ hashCode() → core::int*; -> core::Object::hashCode
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ toString() → core::String*; -> core::Object::toString
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
-  abstract member-signature get /*isNullableByDefault, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature operator /*isLegacy, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get /*isLegacy, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get /*isLegacy, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ toString() → core::String*; -> core::Object::toString
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get /*isLegacy, from org-dartlang-testcase:///flutter_issue_63029_lib2.dart */ runtimeType() → core::Type*; -> core::Object::runtimeType
 }
 class F extends self::_F&B&D {
   synthetic constructor •() → self::F
diff --git a/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_out.dart.weak.expect b/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_out.dart.weak.expect
index dd9e9f0..b2fa606 100644
--- a/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_out.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_out.dart.weak.expect
@@ -34,13 +34,13 @@
   synthetic constructor •() → self::Class4b
     : super core::Object::•()
     ;
-  abstract member-signature operator /*isNullableByDefault*/ ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
 }
 class Class4c extends core::Object implements inh::GenericInterface<core::num?> {
   synthetic constructor •() → self::Class4c
     : super core::Object::•()
     ;
-  abstract member-signature operator /*isNullableByDefault*/ ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
 }
 class Class4d extends inh::LegacyClass4 implements inh::GenericInterface<core::num> {
   synthetic constructor •() → self::Class4d
diff --git a/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_out.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_out.dart.weak.transformed.expect
index 4b67f47..b6b56b8 100644
--- a/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_out.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/inheritance_from_opt_out.dart.weak.transformed.expect
@@ -34,13 +34,13 @@
   synthetic constructor •() → self::Class4b
     : super core::Object::•()
     ;
-  abstract member-signature operator /*isNullableByDefault*/ ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
 }
 class Class4c extends core::Object implements inh::GenericInterface<core::num?> {
   synthetic constructor •() → self::Class4c
     : super core::Object::•()
     ;
-  abstract member-signature operator /*isNullableByDefault*/ ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
 }
 class Class4d extends inh::LegacyClass4 implements inh::GenericInterface<core::num> {
   synthetic constructor •() → self::Class4d
diff --git a/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_out.dart.weak.expect b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_out.dart.weak.expect
index 70ef7e5..8a40f19 100644
--- a/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_out.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_out.dart.weak.expect
@@ -9,7 +9,7 @@
   const synthetic constructor •() → self::_Class&Object&Mixin
     : super core::Object::•()
     ;
-  abstract member-signature operator /*isNullableByDefault*/ ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
 }
 class Class extends self::_Class&Object&Mixin {
   synthetic constructor •() → self::Class
diff --git a/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_out.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_out.dart.weak.transformed.expect
index ea35440..75f6938 100644
--- a/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_out.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/mixin_from_opt_out.dart.weak.transformed.expect
@@ -9,18 +9,18 @@
   const synthetic constructor •() → self::_Class&Object&Mixin
     : super core::Object::•()
     ;
-  abstract member-signature operator /*isNullableByDefault, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ ==(dynamic other) → core::bool*; -> core::Object::==
-  method /*isNullableByDefault, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ method(core::int* i) → core::int*
+  abstract member-signature operator /*isLegacy, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ ==(dynamic other) → core::bool*; -> core::Object::==
+  method /*isLegacy, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ method(core::int* i) → core::int*
     return let final core::int* #t1 = i in #t1.{core::num::==}(null) ?{core::int*} 0 : #t1;
-  abstract member-signature get /*isNullableByDefault, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ _identityHashCode() → core::int*; -> core::Object::_identityHashCode
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
-  abstract member-signature get /*isNullableByDefault, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ hashCode() → core::int*; -> core::Object::hashCode
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ toString() → core::String*; -> core::Object::toString
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
-  abstract member-signature get /*isNullableByDefault, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ runtimeType() → core::Type*; -> core::Object::runtimeType
+  abstract member-signature get /*isLegacy, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get /*isLegacy, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ toString() → core::String*; -> core::Object::toString
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get /*isLegacy, from org-dartlang-testcase:///mixin_from_opt_out_lib.dart */ runtimeType() → core::Type*; -> core::Object::runtimeType
 }
 class Class extends self::_Class&Object&Mixin {
   synthetic constructor •() → self::Class
diff --git a/pkg/front_end/testcases/nnbd_mixed/object_bound_factory/main.dart.weak.expect b/pkg/front_end/testcases/nnbd_mixed/object_bound_factory/main.dart.weak.expect
index d4f279e..567675d 100644
--- a/pkg/front_end/testcases/nnbd_mixed/object_bound_factory/main.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/object_bound_factory/main.dart.weak.expect
@@ -34,7 +34,7 @@
 import "dart:core" as core;
 
 class Class1<T extends core::Object? = core::Object?> extends core::Object /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::Class1::redirect, opt::Class1::constRedirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::Class1::redirect, opt::Class1::constRedirect]/*isLegacy*/;
   const constructor _() → opt::Class1<opt::Class1::T%>
     : super core::Object::•()
     ;
@@ -46,7 +46,7 @@
     return new opt::Class1::_<opt::Class1::fact::T%>();
 }
 class Class2<T extends core::Object = core::Object> extends core::Object /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::Class2::redirect, opt::Class2::constRedirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::Class2::redirect, opt::Class2::constRedirect]/*isLegacy*/;
   const constructor _() → opt::Class2<opt::Class2::T>
     : super core::Object::•()
     ;
@@ -58,7 +58,7 @@
     return new opt::Class2::_<opt::Class2::fact::T>();
 }
 class Class3<T extends core::String = core::String> extends core::Object /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::Class3::redirect, opt::Class3::constRedirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::Class3::redirect, opt::Class3::constRedirect]/*isLegacy*/;
   const constructor _() → opt::Class3<opt::Class3::T>
     : super core::Object::•()
     ;
@@ -70,7 +70,7 @@
     return new opt::Class3::_<opt::Class3::fact::T>();
 }
 class Class4<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::Class4::redirect, opt::Class4::constRedirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::Class4::redirect, opt::Class4::constRedirect]/*isLegacy*/;
   const constructor _() → opt::Class4<opt::Class4::T%>
     : super core::Object::•()
     ;
@@ -82,7 +82,7 @@
     return new opt::Class4::_<opt::Class4::fact::T%>();
 }
 class Class5<T extends dynamic = dynamic> extends core::Object /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::Class5::redirect, opt::Class5::constRedirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::Class5::redirect, opt::Class5::constRedirect]/*isLegacy*/;
   const constructor _() → opt::Class5<opt::Class5::T%>
     : super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd_mixed/object_bound_factory/main.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/object_bound_factory/main.dart.weak.transformed.expect
index b06177a..789e4fb 100644
--- a/pkg/front_end/testcases/nnbd_mixed/object_bound_factory/main.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/object_bound_factory/main.dart.weak.transformed.expect
@@ -34,7 +34,7 @@
 import "dart:core" as core;
 
 class Class1<T extends core::Object? = core::Object?> extends core::Object /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::Class1::redirect, opt::Class1::constRedirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::Class1::redirect, opt::Class1::constRedirect]/*isLegacy*/;
   const constructor _() → opt::Class1<opt::Class1::T%>
     : super core::Object::•()
     ;
@@ -46,7 +46,7 @@
     return new opt::Class1::_<opt::Class1::fact::T%>();
 }
 class Class2<T extends core::Object = core::Object> extends core::Object /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::Class2::redirect, opt::Class2::constRedirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::Class2::redirect, opt::Class2::constRedirect]/*isLegacy*/;
   const constructor _() → opt::Class2<opt::Class2::T>
     : super core::Object::•()
     ;
@@ -58,7 +58,7 @@
     return new opt::Class2::_<opt::Class2::fact::T>();
 }
 class Class3<T extends core::String = core::String> extends core::Object /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::Class3::redirect, opt::Class3::constRedirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::Class3::redirect, opt::Class3::constRedirect]/*isLegacy*/;
   const constructor _() → opt::Class3<opt::Class3::T>
     : super core::Object::•()
     ;
@@ -70,7 +70,7 @@
     return new opt::Class3::_<opt::Class3::fact::T>();
 }
 class Class4<T extends core::Object? = dynamic> extends core::Object /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::Class4::redirect, opt::Class4::constRedirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::Class4::redirect, opt::Class4::constRedirect]/*isLegacy*/;
   const constructor _() → opt::Class4<opt::Class4::T%>
     : super core::Object::•()
     ;
@@ -82,7 +82,7 @@
     return new opt::Class4::_<opt::Class4::fact::T%>();
 }
 class Class5<T extends dynamic = dynamic> extends core::Object /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::Class5::redirect, opt::Class5::constRedirect]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::Class5::redirect, opt::Class5::constRedirect]/*isLegacy*/;
   const constructor _() → opt::Class5<opt::Class5::T%>
     : super core::Object::•()
     ;
diff --git a/pkg/front_end/testcases/nnbd_mixed/object_bound_redirecting_factory/main.dart.weak.expect b/pkg/front_end/testcases/nnbd_mixed/object_bound_redirecting_factory/main.dart.weak.expect
index cf96979..37158e0 100644
--- a/pkg/front_end/testcases/nnbd_mixed/object_bound_redirecting_factory/main.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/object_bound_redirecting_factory/main.dart.weak.expect
@@ -50,7 +50,7 @@
     ;
 }
 class CP<T extends core::Object = core::Object> extends opt::P<opt::CP::T> /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::CP::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::CP::•]/*isLegacy*/;
   const constructor _(core::Object token) → opt::CP<opt::CP::T>
     : super opt::P::_(token)
     ;
@@ -63,7 +63,7 @@
     ;
 }
 class VP<T extends core::Object = core::Object> extends opt::P<opt::VP::T> /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::VP::forToken]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::VP::forToken]/*isLegacy*/;
   const constructor _(core::Object token, opt::VP::T useValue) → opt::VP<opt::VP::T>
     : super opt::P::_(token)
     ;
diff --git a/pkg/front_end/testcases/nnbd_mixed/object_bound_redirecting_factory/main.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/object_bound_redirecting_factory/main.dart.weak.transformed.expect
index 69f70c8..49ef11a 100644
--- a/pkg/front_end/testcases/nnbd_mixed/object_bound_redirecting_factory/main.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/object_bound_redirecting_factory/main.dart.weak.transformed.expect
@@ -50,7 +50,7 @@
     ;
 }
 class CP<T extends core::Object = core::Object> extends opt::P<opt::CP::T> /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::CP::•]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::CP::•]/*isLegacy*/;
   const constructor _(core::Object token) → opt::CP<opt::CP::T>
     : super opt::P::_(token)
     ;
@@ -63,7 +63,7 @@
     ;
 }
 class VP<T extends core::Object = core::Object> extends opt::P<opt::VP::T> /*hasConstConstructor*/  {
-  static field dynamic _redirecting# = <dynamic>[opt::VP::forToken]/*isNullableByDefault*/;
+  static field dynamic _redirecting# = <dynamic>[opt::VP::forToken]/*isLegacy*/;
   const constructor _(core::Object token, opt::VP::T useValue) → opt::VP<opt::VP::T>
     : super opt::P::_(token)
     ;
diff --git a/pkg/front_end/testcases/nnbd_mixed/required_name_override.dart.weak.expect b/pkg/front_end/testcases/nnbd_mixed/required_name_override.dart.weak.expect
index 310bd85..eea3841 100644
--- a/pkg/front_end/testcases/nnbd_mixed/required_name_override.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/required_name_override.dart.weak.expect
@@ -36,7 +36,7 @@
   method test_default({required core::int? i = #C1}) → void {}
   method test_nondefault({required core::int? i = #C1}) → void {}
   method test_legacy({required core::int? i = #C1}) → void {}
-  abstract member-signature operator /*isNullableByDefault*/ ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
 }
 static method main() → dynamic {
   new self::A::•().{self::A::test_default}(i: 1);
diff --git a/pkg/front_end/testcases/nnbd_mixed/required_name_override.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/required_name_override.dart.weak.transformed.expect
index 310bd85..eea3841 100644
--- a/pkg/front_end/testcases/nnbd_mixed/required_name_override.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/required_name_override.dart.weak.transformed.expect
@@ -36,7 +36,7 @@
   method test_default({required core::int? i = #C1}) → void {}
   method test_nondefault({required core::int? i = #C1}) → void {}
   method test_legacy({required core::int? i = #C1}) → void {}
-  abstract member-signature operator /*isNullableByDefault*/ ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
 }
 static method main() → dynamic {
   new self::A::•().{self::A::test_default}(i: 1);
diff --git a/pkg/front_end/testcases/nnbd_mixed/required_parameter_mixed_from_opt_out.dart.weak.expect b/pkg/front_end/testcases/nnbd_mixed/required_parameter_mixed_from_opt_out.dart.weak.expect
index 8c936d9..4cc02b1 100644
--- a/pkg/front_end/testcases/nnbd_mixed/required_parameter_mixed_from_opt_out.dart.weak.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/required_parameter_mixed_from_opt_out.dart.weak.expect
@@ -15,9 +15,9 @@
   synthetic constructor •() → self::_Class&Super&Mixin
     : super self::Super::•()
     ;
-  forwarding-stub method /*isNullableByDefault*/ method({covariant core::int* named = #C1}) → void
+  forwarding-stub method /*isLegacy*/ method({covariant core::int* named = #C1}) → void
     return super.{self::Super::method}(named: named);
-  abstract member-signature operator /*isNullableByDefault*/ ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature operator /*isLegacy*/ ==(dynamic other) → core::bool*; -> core::Object::==
 }
 class Class extends self::_Class&Super&Mixin {
   synthetic constructor •() → self::Class
diff --git a/pkg/front_end/testcases/nnbd_mixed/required_parameter_mixed_from_opt_out.dart.weak.transformed.expect b/pkg/front_end/testcases/nnbd_mixed/required_parameter_mixed_from_opt_out.dart.weak.transformed.expect
index 5db65ce..36edcc8 100644
--- a/pkg/front_end/testcases/nnbd_mixed/required_parameter_mixed_from_opt_out.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/nnbd_mixed/required_parameter_mixed_from_opt_out.dart.weak.transformed.expect
@@ -15,17 +15,17 @@
   synthetic constructor •() → self::_Class&Super&Mixin
     : super self::Super::•()
     ;
-  method /*isNullableByDefault, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ method({covariant core::int* named = #C1}) → void {}
-  abstract member-signature operator /*isNullableByDefault, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ ==(dynamic other) → core::bool*; -> core::Object::==
-  abstract member-signature get /*isNullableByDefault, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ _identityHashCode() → core::int*; -> core::Object::_identityHashCode
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
-  abstract member-signature get /*isNullableByDefault, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ hashCode() → core::int*; -> core::Object::hashCode
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ toString() → core::String*; -> core::Object::toString
-  abstract member-signature method /*isNullableByDefault, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
-  abstract member-signature get /*isNullableByDefault, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ runtimeType() → core::Type*; -> core::Object::runtimeType
+  method /*isLegacy, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ method({covariant core::int* named = #C1}) → void {}
+  abstract member-signature operator /*isLegacy, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ ==(dynamic other) → core::bool*; -> core::Object::==
+  abstract member-signature get /*isLegacy, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ _identityHashCode() → core::int*; -> core::Object::_identityHashCode
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ _instanceOf(dynamic instantiatorTypeArguments, dynamic functionTypeArguments, dynamic type) → core::bool*; -> core::Object::_instanceOf
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ _simpleInstanceOf(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOf
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ _simpleInstanceOfTrue(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfTrue
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ _simpleInstanceOfFalse(dynamic type) → core::bool*; -> core::Object::_simpleInstanceOfFalse
+  abstract member-signature get /*isLegacy, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ hashCode() → core::int*; -> core::Object::hashCode
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ toString() → core::String*; -> core::Object::toString
+  abstract member-signature method /*isLegacy, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ noSuchMethod(core::Invocation* invocation) → dynamic; -> core::Object::noSuchMethod
+  abstract member-signature get /*isLegacy, from org-dartlang-testcase:///required_parameter_mixed_from_opt_out_lib.dart */ runtimeType() → core::Type*; -> core::Object::runtimeType
 }
 class Class extends self::_Class&Super&Mixin {
   synthetic constructor •() → self::Class
diff --git a/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.strong.expect b/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.strong.expect
index e404600..1f7ce47 100644
--- a/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.strong.expect
+++ b/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.strong.expect
@@ -57,13 +57,13 @@
   synthetic constructor •({required core::int? numberOfWhiskers, core::int? numberOfLegs}) → self::Cat
     : self::Cat::numberOfWhiskers = numberOfWhiskers, super self::Animal::•(numberOfLegs)
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Animal::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///copy_with_call_sites.dartCat".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int? numberOfLegs, core::int? numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int? numberOfLegs, core::int? numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 class Foo extends core::Object {
@@ -83,13 +83,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///copy_with_call_sites.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.strong.transformed.expect b/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.strong.transformed.expect
index 90ed8ba..db25a4a 100644
--- a/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.strong.transformed.expect
@@ -57,13 +57,13 @@
   synthetic constructor •({required core::int? numberOfWhiskers, core::int? numberOfLegs}) → self::Cat
     : self::Cat::numberOfWhiskers = numberOfWhiskers, super self::Animal::•(numberOfLegs)
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Animal::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///copy_with_call_sites.dartCat".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int? numberOfLegs, core::int? numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int? numberOfLegs, core::int? numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 class Foo extends core::Object {
@@ -83,13 +83,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///copy_with_call_sites.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.weak.expect b/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.weak.expect
index e404600..1f7ce47 100644
--- a/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.weak.expect
+++ b/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.weak.expect
@@ -57,13 +57,13 @@
   synthetic constructor •({required core::int? numberOfWhiskers, core::int? numberOfLegs}) → self::Cat
     : self::Cat::numberOfWhiskers = numberOfWhiskers, super self::Animal::•(numberOfLegs)
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Animal::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///copy_with_call_sites.dartCat".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int? numberOfLegs, core::int? numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int? numberOfLegs, core::int? numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 class Foo extends core::Object {
@@ -83,13 +83,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///copy_with_call_sites.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.weak.transformed.expect b/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.weak.transformed.expect
index 90ed8ba..db25a4a 100644
--- a/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/value_class/copy_with_call_sites.dart.weak.transformed.expect
@@ -57,13 +57,13 @@
   synthetic constructor •({required core::int? numberOfWhiskers, core::int? numberOfLegs}) → self::Cat
     : self::Cat::numberOfWhiskers = numberOfWhiskers, super self::Animal::•(numberOfLegs)
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Animal::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///copy_with_call_sites.dartCat".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int? numberOfLegs, core::int? numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int? numberOfLegs, core::int? numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 class Foo extends core::Object {
@@ -83,13 +83,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///copy_with_call_sites.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/empty.dart.strong.expect b/pkg/front_end/testcases/value_class/empty.dart.strong.expect
index ea8f20e..ad09297 100644
--- a/pkg/front_end/testcases/value_class/empty.dart.strong.expect
+++ b/pkg/front_end/testcases/value_class/empty.dart.strong.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::EmptyClass
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::EmptyClass;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///empty.dartEmptyClass".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "EmptyClass()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::EmptyClass::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/empty.dart.strong.transformed.expect b/pkg/front_end/testcases/value_class/empty.dart.strong.transformed.expect
index 0ce153d..ccb643b 100644
--- a/pkg/front_end/testcases/value_class/empty.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/value_class/empty.dart.strong.transformed.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::EmptyClass
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::EmptyClass;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///empty.dartEmptyClass".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "EmptyClass()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::EmptyClass::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/empty.dart.weak.expect b/pkg/front_end/testcases/value_class/empty.dart.weak.expect
index ea8f20e..ad09297 100644
--- a/pkg/front_end/testcases/value_class/empty.dart.weak.expect
+++ b/pkg/front_end/testcases/value_class/empty.dart.weak.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::EmptyClass
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::EmptyClass;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///empty.dartEmptyClass".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "EmptyClass()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::EmptyClass::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/empty.dart.weak.transformed.expect b/pkg/front_end/testcases/value_class/empty.dart.weak.transformed.expect
index 0ce153d..ccb643b 100644
--- a/pkg/front_end/testcases/value_class/empty.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/value_class/empty.dart.weak.transformed.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::EmptyClass
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::EmptyClass;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///empty.dartEmptyClass".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "EmptyClass()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::EmptyClass::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/explicit_mixin.dart.strong.expect b/pkg/front_end/testcases/value_class/explicit_mixin.dart.strong.expect
index 8f5b282..1dddd63 100644
--- a/pkg/front_end/testcases/value_class/explicit_mixin.dart.strong.expect
+++ b/pkg/front_end/testcases/value_class/explicit_mixin.dart.strong.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class B extends core::Object {
@@ -42,13 +42,13 @@
   synthetic constructor •() → self::F
     : super self::B::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::F;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartF".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "F()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::F::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/explicit_mixin.dart.strong.transformed.expect b/pkg/front_end/testcases/value_class/explicit_mixin.dart.strong.transformed.expect
index f6df7f8..3265e24 100644
--- a/pkg/front_end/testcases/value_class/explicit_mixin.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/value_class/explicit_mixin.dart.strong.transformed.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class B extends core::Object {
@@ -37,26 +37,26 @@
   synthetic constructor •() → self::E
     : super self::B::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class F extends self::B implements self::C /*isEliminatedMixin*/  {
   synthetic constructor •() → self::F
     : super self::B::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::F;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartF".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "F()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::F::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/explicit_mixin.dart.weak.expect b/pkg/front_end/testcases/value_class/explicit_mixin.dart.weak.expect
index 8f5b282..1dddd63 100644
--- a/pkg/front_end/testcases/value_class/explicit_mixin.dart.weak.expect
+++ b/pkg/front_end/testcases/value_class/explicit_mixin.dart.weak.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class B extends core::Object {
@@ -42,13 +42,13 @@
   synthetic constructor •() → self::F
     : super self::B::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::F;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartF".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "F()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::F::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/explicit_mixin.dart.weak.transformed.expect b/pkg/front_end/testcases/value_class/explicit_mixin.dart.weak.transformed.expect
index f6df7f8..3265e24 100644
--- a/pkg/front_end/testcases/value_class/explicit_mixin.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/value_class/explicit_mixin.dart.weak.transformed.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class B extends core::Object {
@@ -37,26 +37,26 @@
   synthetic constructor •() → self::E
     : super self::B::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class F extends self::B implements self::C /*isEliminatedMixin*/  {
   synthetic constructor •() → self::F
     : super self::B::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::F;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///explicit_mixin.dartF".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "F()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::F::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/non_final_field_error.dart.strong.expect b/pkg/front_end/testcases/value_class/non_final_field_error.dart.strong.expect
index 106c4ea..a306bf0 100644
--- a/pkg/front_end/testcases/value_class/non_final_field_error.dart.strong.expect
+++ b/pkg/front_end/testcases/value_class/non_final_field_error.dart.strong.expect
@@ -17,13 +17,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_final_field_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/non_final_field_error.dart.strong.transformed.expect b/pkg/front_end/testcases/value_class/non_final_field_error.dart.strong.transformed.expect
index 106c4ea..a306bf0 100644
--- a/pkg/front_end/testcases/value_class/non_final_field_error.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/value_class/non_final_field_error.dart.strong.transformed.expect
@@ -17,13 +17,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_final_field_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/non_final_field_error.dart.weak.expect b/pkg/front_end/testcases/value_class/non_final_field_error.dart.weak.expect
index 106c4ea..a306bf0 100644
--- a/pkg/front_end/testcases/value_class/non_final_field_error.dart.weak.expect
+++ b/pkg/front_end/testcases/value_class/non_final_field_error.dart.weak.expect
@@ -17,13 +17,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_final_field_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/non_final_field_error.dart.weak.transformed.expect b/pkg/front_end/testcases/value_class/non_final_field_error.dart.weak.transformed.expect
index 106c4ea..a306bf0 100644
--- a/pkg/front_end/testcases/value_class/non_final_field_error.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/value_class/non_final_field_error.dart.weak.transformed.expect
@@ -17,13 +17,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_final_field_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.strong.expect b/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.strong.expect
index 8b97d06..d077f3e 100644
--- a/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.strong.expect
+++ b/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.strong.expect
@@ -18,13 +18,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_value_extends_value_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 class Cat extends self::Animal {
diff --git a/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.strong.transformed.expect b/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.strong.transformed.expect
index 8b97d06..d077f3e 100644
--- a/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.strong.transformed.expect
@@ -18,13 +18,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_value_extends_value_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 class Cat extends self::Animal {
diff --git a/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.weak.expect b/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.weak.expect
index 8b97d06..d077f3e 100644
--- a/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.weak.expect
+++ b/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.weak.expect
@@ -18,13 +18,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_value_extends_value_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 class Cat extends self::Animal {
diff --git a/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.weak.transformed.expect b/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.weak.transformed.expect
index 8b97d06..d077f3e 100644
--- a/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/value_class/non_value_extends_value_error.dart.weak.transformed.expect
@@ -18,13 +18,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_value_extends_value_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 class Cat extends self::Animal {
diff --git a/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.strong.expect b/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.strong.expect
index c12b1c3..21c901e 100644
--- a/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.strong.expect
+++ b/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.strong.expect
@@ -23,13 +23,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_value_implements_value_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 class Cat extends core::Object implements self::Animal {
diff --git a/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.strong.transformed.expect b/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.strong.transformed.expect
index c12b1c3..21c901e 100644
--- a/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.strong.transformed.expect
@@ -23,13 +23,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_value_implements_value_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 class Cat extends core::Object implements self::Animal {
diff --git a/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.weak.expect b/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.weak.expect
index c12b1c3..21c901e 100644
--- a/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.weak.expect
+++ b/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.weak.expect
@@ -23,13 +23,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_value_implements_value_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 class Cat extends core::Object implements self::Animal {
diff --git a/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.weak.transformed.expect b/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.weak.transformed.expect
index c12b1c3..21c901e 100644
--- a/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/value_class/non_value_implements_value_error.dart.weak.transformed.expect
@@ -23,13 +23,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///non_value_implements_value_error.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 class Cat extends core::Object implements self::Animal {
diff --git a/pkg/front_end/testcases/value_class/simple.dart.strong.expect b/pkg/front_end/testcases/value_class/simple.dart.strong.expect
index 67bbec1..9c011f1 100644
--- a/pkg/front_end/testcases/value_class/simple.dart.strong.expect
+++ b/pkg/front_end/testcases/value_class/simple.dart.strong.expect
@@ -39,13 +39,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///simple.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/simple.dart.strong.transformed.expect b/pkg/front_end/testcases/value_class/simple.dart.strong.transformed.expect
index 88adc14..f8dee0a 100644
--- a/pkg/front_end/testcases/value_class/simple.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/value_class/simple.dart.strong.transformed.expect
@@ -39,13 +39,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///simple.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/simple.dart.weak.expect b/pkg/front_end/testcases/value_class/simple.dart.weak.expect
index 67bbec1..9c011f1 100644
--- a/pkg/front_end/testcases/value_class/simple.dart.weak.expect
+++ b/pkg/front_end/testcases/value_class/simple.dart.weak.expect
@@ -39,13 +39,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///simple.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/simple.dart.weak.transformed.expect b/pkg/front_end/testcases/value_class/simple.dart.weak.transformed.expect
index 88adc14..f8dee0a 100644
--- a/pkg/front_end/testcases/value_class/simple.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/value_class/simple.dart.weak.transformed.expect
@@ -39,13 +39,13 @@
   synthetic constructor •({required core::int numberOfLegs}) → self::Animal
     : self::Animal::numberOfLegs = numberOfLegs, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Animal && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Animal}.{self::Animal::numberOfLegs});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine("org-dartlang-testcase:///simple.dartAnimal".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Animal(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs}) → dynamic
     return new self::Animal::•(numberOfLegs: numberOfLegs);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/value_extends_non_value.dart.strong.expect b/pkg/front_end/testcases/value_class/value_extends_non_value.dart.strong.expect
index 8ab2483..9ba8a2f 100644
--- a/pkg/front_end/testcases/value_class/value_extends_non_value.dart.strong.expect
+++ b/pkg/front_end/testcases/value_class/value_extends_non_value.dart.strong.expect
@@ -45,13 +45,13 @@
   synthetic constructor •({required core::int numberOfWhiskers, core::int numberOfLegs}) → self::Cat
     : self::Cat::numberOfWhiskers = numberOfWhiskers, super self::Animal::•(numberOfLegs)
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Animal::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_extends_non_value.dartCat".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/value_extends_non_value.dart.strong.transformed.expect b/pkg/front_end/testcases/value_class/value_extends_non_value.dart.strong.transformed.expect
index 2227f34..cac374d 100644
--- a/pkg/front_end/testcases/value_class/value_extends_non_value.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/value_class/value_extends_non_value.dart.strong.transformed.expect
@@ -45,13 +45,13 @@
   synthetic constructor •({required core::int numberOfWhiskers, core::int numberOfLegs}) → self::Cat
     : self::Cat::numberOfWhiskers = numberOfWhiskers, super self::Animal::•(numberOfLegs)
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Animal::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_extends_non_value.dartCat".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/value_extends_non_value.dart.weak.expect b/pkg/front_end/testcases/value_class/value_extends_non_value.dart.weak.expect
index 8ab2483..9ba8a2f 100644
--- a/pkg/front_end/testcases/value_class/value_extends_non_value.dart.weak.expect
+++ b/pkg/front_end/testcases/value_class/value_extends_non_value.dart.weak.expect
@@ -45,13 +45,13 @@
   synthetic constructor •({required core::int numberOfWhiskers, core::int numberOfLegs}) → self::Cat
     : self::Cat::numberOfWhiskers = numberOfWhiskers, super self::Animal::•(numberOfLegs)
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Animal::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_extends_non_value.dartCat".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/value_extends_non_value.dart.weak.transformed.expect b/pkg/front_end/testcases/value_class/value_extends_non_value.dart.weak.transformed.expect
index 2227f34..cac374d 100644
--- a/pkg/front_end/testcases/value_class/value_extends_non_value.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/value_class/value_extends_non_value.dart.weak.transformed.expect
@@ -45,13 +45,13 @@
   synthetic constructor •({required core::int numberOfWhiskers, core::int numberOfLegs}) → self::Cat
     : self::Cat::numberOfWhiskers = numberOfWhiskers, super self::Animal::•(numberOfLegs)
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Animal::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Animal::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_extends_non_value.dartCat".{core::String::hashCode}, this.{self::Animal::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Animal::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.strong.expect b/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.strong.expect
index 95e0356..e039566 100644
--- a/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.strong.expect
+++ b/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.strong.expect
@@ -27,13 +27,13 @@
   synthetic constructor •() → self::Cat
     : super self::Animal::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_extends_non_value_error.dartCat".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::Cat::•();
 }
 class Animal2 extends core::Object {
@@ -46,13 +46,13 @@
   synthetic constructor •() → self::Cat2
     : super self::Animal2::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat2;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_extends_non_value_error.dartCat2".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat2()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::Cat2::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.strong.transformed.expect b/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.strong.transformed.expect
index b55acf5..d80dd8f 100644
--- a/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.strong.transformed.expect
@@ -27,13 +27,13 @@
   synthetic constructor •() → self::Cat
     : super self::Animal::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_extends_non_value_error.dartCat".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::Cat::•();
 }
 class Animal2 extends core::Object {
@@ -46,13 +46,13 @@
   synthetic constructor •() → self::Cat2
     : super self::Animal2::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat2;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_extends_non_value_error.dartCat2".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat2()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::Cat2::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.weak.expect b/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.weak.expect
index 95e0356..e039566 100644
--- a/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.weak.expect
+++ b/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.weak.expect
@@ -27,13 +27,13 @@
   synthetic constructor •() → self::Cat
     : super self::Animal::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_extends_non_value_error.dartCat".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::Cat::•();
 }
 class Animal2 extends core::Object {
@@ -46,13 +46,13 @@
   synthetic constructor •() → self::Cat2
     : super self::Animal2::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat2;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_extends_non_value_error.dartCat2".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat2()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::Cat2::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.weak.transformed.expect b/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.weak.transformed.expect
index b55acf5..d80dd8f 100644
--- a/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/value_class/value_extends_non_value_error.dart.weak.transformed.expect
@@ -27,13 +27,13 @@
   synthetic constructor •() → self::Cat
     : super self::Animal::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_extends_non_value_error.dartCat".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::Cat::•();
 }
 class Animal2 extends core::Object {
@@ -46,13 +46,13 @@
   synthetic constructor •() → self::Cat2
     : super self::Animal2::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat2;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_extends_non_value_error.dartCat2".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat2()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::Cat2::•();
 }
 static method main() → dynamic {}
diff --git a/pkg/front_end/testcases/value_class/value_implements_non_value.dart.strong.expect b/pkg/front_end/testcases/value_class/value_implements_non_value.dart.strong.expect
index ea9e6be..e8f803a 100644
--- a/pkg/front_end/testcases/value_class/value_implements_non_value.dart.strong.expect
+++ b/pkg/front_end/testcases/value_class/value_implements_non_value.dart.strong.expect
@@ -87,13 +87,13 @@
   synthetic constructor •({required core::int numberOfLegs, required core::int numberOfWhiskers}) → self::Cat
     : self::Cat::numberOfLegs = numberOfLegs, self::Cat::numberOfWhiskers = numberOfWhiskers, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Cat::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_implements_non_value.dartCat".{core::String::hashCode}, this.{self::Cat::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Cat::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 abstract class Animal2 extends core::Object {
@@ -108,13 +108,13 @@
   synthetic constructor •({required core::int numberOfLegs, required core::int numberOfWhiskers}) → self::Cat2
     : self::Cat2::numberOfLegs = numberOfLegs, self::Cat2::numberOfWhiskers = numberOfWhiskers, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat2 && this.{self::Cat2::numberOfLegs}.{core::num::==}(other{self::Cat2}.{self::Cat2::numberOfLegs}) && this.{self::Cat2::numberOfWhiskers}.{core::num::==}(other{self::Cat2}.{self::Cat2::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_implements_non_value.dartCat2".{core::String::hashCode}, this.{self::Cat2::numberOfLegs}.{core::num::hashCode}), this.{self::Cat2::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat2(numberOfLegs: ${this.{self::Cat2::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat2::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat2::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/value_implements_non_value.dart.strong.transformed.expect b/pkg/front_end/testcases/value_class/value_implements_non_value.dart.strong.transformed.expect
index dfd6ccf..bb58694 100644
--- a/pkg/front_end/testcases/value_class/value_implements_non_value.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/value_class/value_implements_non_value.dart.strong.transformed.expect
@@ -87,13 +87,13 @@
   synthetic constructor •({required core::int numberOfLegs, required core::int numberOfWhiskers}) → self::Cat
     : self::Cat::numberOfLegs = numberOfLegs, self::Cat::numberOfWhiskers = numberOfWhiskers, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Cat::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_implements_non_value.dartCat".{core::String::hashCode}, this.{self::Cat::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Cat::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 abstract class Animal2 extends core::Object {
@@ -108,13 +108,13 @@
   synthetic constructor •({required core::int numberOfLegs, required core::int numberOfWhiskers}) → self::Cat2
     : self::Cat2::numberOfLegs = numberOfLegs, self::Cat2::numberOfWhiskers = numberOfWhiskers, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat2 && this.{self::Cat2::numberOfLegs}.{core::num::==}(other{self::Cat2}.{self::Cat2::numberOfLegs}) && this.{self::Cat2::numberOfWhiskers}.{core::num::==}(other{self::Cat2}.{self::Cat2::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_implements_non_value.dartCat2".{core::String::hashCode}, this.{self::Cat2::numberOfLegs}.{core::num::hashCode}), this.{self::Cat2::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat2(numberOfLegs: ${this.{self::Cat2::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat2::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat2::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/value_implements_non_value.dart.weak.expect b/pkg/front_end/testcases/value_class/value_implements_non_value.dart.weak.expect
index ea9e6be..e8f803a 100644
--- a/pkg/front_end/testcases/value_class/value_implements_non_value.dart.weak.expect
+++ b/pkg/front_end/testcases/value_class/value_implements_non_value.dart.weak.expect
@@ -87,13 +87,13 @@
   synthetic constructor •({required core::int numberOfLegs, required core::int numberOfWhiskers}) → self::Cat
     : self::Cat::numberOfLegs = numberOfLegs, self::Cat::numberOfWhiskers = numberOfWhiskers, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Cat::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_implements_non_value.dartCat".{core::String::hashCode}, this.{self::Cat::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Cat::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 abstract class Animal2 extends core::Object {
@@ -108,13 +108,13 @@
   synthetic constructor •({required core::int numberOfLegs, required core::int numberOfWhiskers}) → self::Cat2
     : self::Cat2::numberOfLegs = numberOfLegs, self::Cat2::numberOfWhiskers = numberOfWhiskers, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat2 && this.{self::Cat2::numberOfLegs}.{core::num::==}(other{self::Cat2}.{self::Cat2::numberOfLegs}) && this.{self::Cat2::numberOfWhiskers}.{core::num::==}(other{self::Cat2}.{self::Cat2::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_implements_non_value.dartCat2".{core::String::hashCode}, this.{self::Cat2::numberOfLegs}.{core::num::hashCode}), this.{self::Cat2::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat2(numberOfLegs: ${this.{self::Cat2::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat2::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat2::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/value_implements_non_value.dart.weak.transformed.expect b/pkg/front_end/testcases/value_class/value_implements_non_value.dart.weak.transformed.expect
index dfd6ccf..bb58694 100644
--- a/pkg/front_end/testcases/value_class/value_implements_non_value.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/value_class/value_implements_non_value.dart.weak.transformed.expect
@@ -87,13 +87,13 @@
   synthetic constructor •({required core::int numberOfLegs, required core::int numberOfWhiskers}) → self::Cat
     : self::Cat::numberOfLegs = numberOfLegs, self::Cat::numberOfWhiskers = numberOfWhiskers, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat && this.{self::Cat::numberOfLegs}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfLegs}) && this.{self::Cat::numberOfWhiskers}.{core::num::==}(other{self::Cat}.{self::Cat::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_implements_non_value.dartCat".{core::String::hashCode}, this.{self::Cat::numberOfLegs}.{core::num::hashCode}), this.{self::Cat::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat(numberOfLegs: ${this.{self::Cat::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 abstract class Animal2 extends core::Object {
@@ -108,13 +108,13 @@
   synthetic constructor •({required core::int numberOfLegs, required core::int numberOfWhiskers}) → self::Cat2
     : self::Cat2::numberOfLegs = numberOfLegs, self::Cat2::numberOfWhiskers = numberOfWhiskers, super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::Cat2 && this.{self::Cat2::numberOfLegs}.{core::num::==}(other{self::Cat2}.{self::Cat2::numberOfLegs}) && this.{self::Cat2::numberOfWhiskers}.{core::num::==}(other{self::Cat2}.{self::Cat2::numberOfWhiskers});
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish(val::JenkinsSmiHash::combine(val::JenkinsSmiHash::combine("org-dartlang-testcase:///value_implements_non_value.dartCat2".{core::String::hashCode}, this.{self::Cat2::numberOfLegs}.{core::num::hashCode}), this.{self::Cat2::numberOfWhiskers}.{core::num::hashCode}));
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "Cat2(numberOfLegs: ${this.{self::Cat2::numberOfLegs}.{core::int::toString}()}, numberOfWhiskers: ${this.{self::Cat2::numberOfWhiskers}.{core::int::toString}()})";
-  method /*isNullableByDefault*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
+  method /*isLegacy*/ copyWith({core::int numberOfLegs, core::int numberOfWhiskers}) → dynamic
     return new self::Cat2::•(numberOfLegs: numberOfLegs, numberOfWhiskers: numberOfWhiskers);
 }
 static method main() → dynamic {
diff --git a/pkg/front_end/testcases/value_class/value_mixin_error.dart.strong.expect b/pkg/front_end/testcases/value_class/value_mixin_error.dart.strong.expect
index 5b97acf..5391b61 100644
--- a/pkg/front_end/testcases/value_class/value_mixin_error.dart.strong.expect
+++ b/pkg/front_end/testcases/value_class/value_mixin_error.dart.strong.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_mixin_error.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class B extends core::Object {
diff --git a/pkg/front_end/testcases/value_class/value_mixin_error.dart.strong.transformed.expect b/pkg/front_end/testcases/value_class/value_mixin_error.dart.strong.transformed.expect
index 5b474c0..4bf6fa3 100644
--- a/pkg/front_end/testcases/value_class/value_mixin_error.dart.strong.transformed.expect
+++ b/pkg/front_end/testcases/value_class/value_mixin_error.dart.strong.transformed.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_mixin_error.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class B extends core::Object {
@@ -27,13 +27,13 @@
   synthetic constructor •() → self::_C&B&A
     : super self::B::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_mixin_error.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class C extends self::_C&B&A {
diff --git a/pkg/front_end/testcases/value_class/value_mixin_error.dart.weak.expect b/pkg/front_end/testcases/value_class/value_mixin_error.dart.weak.expect
index 5b97acf..5391b61 100644
--- a/pkg/front_end/testcases/value_class/value_mixin_error.dart.weak.expect
+++ b/pkg/front_end/testcases/value_class/value_mixin_error.dart.weak.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_mixin_error.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class B extends core::Object {
diff --git a/pkg/front_end/testcases/value_class/value_mixin_error.dart.weak.transformed.expect b/pkg/front_end/testcases/value_class/value_mixin_error.dart.weak.transformed.expect
index 5b474c0..4bf6fa3 100644
--- a/pkg/front_end/testcases/value_class/value_mixin_error.dart.weak.transformed.expect
+++ b/pkg/front_end/testcases/value_class/value_mixin_error.dart.weak.transformed.expect
@@ -9,13 +9,13 @@
   synthetic constructor •() → self::A
     : super core::Object::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_mixin_error.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class B extends core::Object {
@@ -27,13 +27,13 @@
   synthetic constructor •() → self::_C&B&A
     : super self::B::•()
     ;
-  operator /*isNullableByDefault*/ ==(core::Object other) → core::bool
+  operator /*isLegacy*/ ==(core::Object other) → core::bool
     return other is self::A;
-  get /*isNullableByDefault*/ hashCode() → core::int
+  get /*isLegacy*/ hashCode() → core::int
     return val::JenkinsSmiHash::finish("org-dartlang-testcase:///value_mixin_error.dartA".{core::String::hashCode});
-  method /*isNullableByDefault*/ toString() → core::String
+  method /*isLegacy*/ toString() → core::String
     return "A()";
-  method /*isNullableByDefault*/ copyWith() → dynamic
+  method /*isLegacy*/ copyWith() → dynamic
     return new self::A::•();
 }
 class C extends self::_C&B&A {
diff --git a/pkg/kernel/lib/text/ast_to_text.dart b/pkg/kernel/lib/text/ast_to_text.dart
index c633646..84c9ce8 100644
--- a/pkg/kernel/lib/text/ast_to_text.dart
+++ b/pkg/kernel/lib/text/ast_to_text.dart
@@ -1102,7 +1102,7 @@
       if (node.isNonNullableByDefault) {
         features.add("isNonNullableByDefault");
       } else {
-        features.add("isNullableByDefault");
+        features.add("isLegacy");
       }
     }
     if ((node.enclosingClass == null &&
@@ -1134,7 +1134,7 @@
       if (node.isNonNullableByDefault) {
         features.add("isNonNullableByDefault");
       } else {
-        features.add("isNullableByDefault");
+        features.add("isLegacy");
       }
     }
     if ((node.enclosingClass == null &&
@@ -1173,7 +1173,7 @@
       if (node.isNonNullableByDefault) {
         features.add("isNonNullableByDefault");
       } else {
-        features.add("isNullableByDefault");
+        features.add("isLegacy");
       }
     }
     if (features.isNotEmpty) {
@@ -1209,7 +1209,7 @@
       if (node.isNonNullableByDefault) {
         features.add("isNonNullableByDefault");
       } else {
-        features.add("isNullableByDefault");
+        features.add("isLegacy");
       }
     }
     if (features.isNotEmpty) {
diff --git a/pkg/vm/testcases/transformations/type_flow/transformer/regress_41452_nnbd_strong.dart.expect b/pkg/vm/testcases/transformations/type_flow/transformer/regress_41452_nnbd_strong.dart.expect
index 7f5cdd6..61cf1bbd 100644
--- a/pkg/vm/testcases/transformations/type_flow/transformer/regress_41452_nnbd_strong.dart.expect
+++ b/pkg/vm/testcases/transformations/type_flow/transformer/regress_41452_nnbd_strong.dart.expect
@@ -23,7 +23,7 @@
       return;
     core::print([@vm.direct-call.metadata=#lib::_SplayTreeNode.left] [@vm.inferred-type.metadata=dart.core::Null? (value: null)] root{self::_SplayTree::Node}.{self::_SplayTreeNode::left});
   }
-[@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasThisUses:false,hasNonThisUses:false,hasTearOffUses:false,getterSelectorId:5]  abstract get /*isNullableByDefault*/ _root() → self::_SplayTree::Node?;
+[@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasThisUses:false,hasNonThisUses:false,hasTearOffUses:false,getterSelectorId:5]  abstract get /*isLegacy*/ _root() → self::_SplayTree::Node?;
 }
 class SplayTreeMap<V extends core::Object? = dynamic> extends self::_SplayTree<self::_SplayTreeMapNode<self::SplayTreeMap::V%>> {
 [@vm.inferred-type.metadata=#lib::_SplayTreeMapNode] [@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasThisUses:false,hasNonThisUses:false,hasTearOffUses:false,methodOrSetterSelectorId:6,getterSelectorId:5]  generic-covariant-impl field self::_SplayTreeMapNode<self::SplayTreeMap::V%>? _root = new self::_SplayTreeMapNode::•<self::SplayTreeMap::V%>();
diff --git a/pkg/vm/testcases/transformations/type_flow/transformer/write_only_field3_nnbd.dart.expect b/pkg/vm/testcases/transformations/type_flow/transformer/write_only_field3_nnbd.dart.expect
index d43e95d..001ee63 100644
--- a/pkg/vm/testcases/transformations/type_flow/transformer/write_only_field3_nnbd.dart.expect
+++ b/pkg/vm/testcases/transformations/type_flow/transformer/write_only_field3_nnbd.dart.expect
@@ -9,7 +9,7 @@
 [@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasThisUses:false,hasTearOffUses:false,methodOrSetterSelectorId:1,getterSelectorId:2]  method use() → dynamic {
     [@vm.direct-call.metadata=#lib::A.x] [@vm.inferred-type.metadata=!? (skip check)] this.{self::A::x} = 3;
   }
-[@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasNonThisUses:false,hasTearOffUses:false,methodOrSetterSelectorId:3]  set /*isNullableByDefault*/ x(core::int value) → void;
+[@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasNonThisUses:false,hasTearOffUses:false,methodOrSetterSelectorId:3]  set /*isLegacy*/ x(core::int value) → void;
 }
 class B extends core::Object {
 [@vm.inferred-type.metadata=dart.core::_Smi (value: 3)] [@vm.procedure-attributes.metadata=methodOrSetterCalledDynamically:false,getterCalledDynamically:false,hasNonThisUses:false,hasTearOffUses:false,methodOrSetterSelectorId:4,getterSelectorId:5] [@vm.unboxing-info.metadata=(i)->i]  late final [setter] field core::int x;
diff --git a/tools/VERSION b/tools/VERSION
index cabd085..d4fff73 100644
--- a/tools/VERSION
+++ b/tools/VERSION
@@ -27,5 +27,5 @@
 MAJOR 2
 MINOR 12
 PATCH 0
-PRERELEASE 86
+PRERELEASE 87
 PRERELEASE_PATCH 0
\ No newline at end of file