[cfe] Group fragments by name when creating builders

This prepares for grouping introductory and augmentation fragments in
one builder and from grouping getters, setters and fields of the name
into a property builder.

Change-Id: If4b6e14876f2b58cc65c8c3a7d22f99a0c7aa8c9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/391963
Commit-Queue: Johnni Winther <[email protected]>
Reviewed-by: Chloe Stefantsova <[email protected]>

Author: johnniwinther

pkg/front_end/lib/src/fragment/constructor.dart

@@ -5,7 +5,9 @@
 part of 'fragment.dart';
 
 class ConstructorFragment implements Fragment, FunctionFragment {
+  @override
   final String name;
+
   final Uri fileUri;
   final int startOffset;
   final int nameOffset;

pkg/front_end/lib/src/fragment/factory.dart

@@ -5,7 +5,9 @@
 part of 'fragment.dart';
 
 class FactoryFragment implements Fragment, FunctionFragment {
+  @override
   final String name;
+
   final Uri fileUri;
   final int startOffset;
   final int nameOffset;

pkg/front_end/lib/src/fragment/field.dart

@@ -5,7 +5,9 @@
 part of 'fragment.dart';
 
 class FieldFragment implements Fragment {
+  @override
   final String name;
+
   final Uri fileUri;
   final int charOffset;
   final int charEndOffset;

pkg/front_end/lib/src/fragment/fragment.dart

@@ -47,5 +47,21 @@ part 'setter.dart';
 part 'typedef.dart';
 
 sealed class Fragment {
+  /// The declared name of this fragment.
+  ///
+  /// For unnamed extensions this is
+  /// [UnnamedExtensionName.unnamedExtensionSentinel].
+  ///
+  /// For setters this is the name without `=`.
+  ///
+  /// The name is used to group introductory fragments with augmenting fragments
+  /// and to group getters, setters, and fields as properties.
+  String get name;
+
+  /// The [Builder] created for this fragment.
+  ///
+  // TODO(johnniwinther): Implement this:
+  /// The builder is shared between introductory fragments and augmenting
+  /// fragments, as well as between getters, setters, and fields.
   Builder get builder;
 }

pkg/front_end/lib/src/fragment/getter.dart

@@ -5,7 +5,9 @@
 part of 'fragment.dart';
 
 class GetterFragment implements Fragment, FunctionFragment {
+  @override
   final String name;
+
   final Uri fileUri;
   final int startOffset;
   final int nameOffset;

pkg/front_end/lib/src/fragment/method.dart

@@ -5,7 +5,9 @@
 part of 'fragment.dart';
 
 class MethodFragment implements Fragment, FunctionFragment {
+  @override
   final String name;
+
   final Uri fileUri;
   final int startOffset;
   final int nameOffset;

pkg/front_end/lib/src/fragment/named_mixin_application.dart

@@ -5,7 +5,9 @@
 part of 'fragment.dart';
 
 class NamedMixinApplicationFragment implements Fragment {
+  @override
   final String name;
+
   final Uri fileUri;
   final int startOffset;
   final int nameOffset;

pkg/front_end/lib/src/fragment/primary_constructor.dart

@@ -5,7 +5,9 @@
 part of 'fragment.dart';
 
 class PrimaryConstructorFragment implements Fragment, FunctionFragment {
+  @override
   final String name;
+
   final Uri fileUri;
   final int startOffset;
   final int? nameOffset;

pkg/front_end/lib/src/fragment/setter.dart

@@ -5,7 +5,9 @@
 part of 'fragment.dart';
 
 class SetterFragment implements Fragment, FunctionFragment {
+  @override
   final String name;
+
   final Uri fileUri;
   final int startOffset;
   final int nameOffset;

pkg/front_end/lib/src/fragment/typedef.dart

@@ -6,7 +6,10 @@ part of 'fragment.dart';
 
 class TypedefFragment implements Fragment {
   final List<MetadataBuilder>? metadata;
+
+  @override
   final String name;
+
   final List<NominalParameterBuilder>? typeParameters;
   final TypeBuilder type;
   final Uri fileUri;