Change the approach of front_end top level inference to match the spec.

pkg/front_end/lib/src/fasta/kernel/body_builder.dart

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library fasta.body_builder;
 
 import '../fasta_codes.dart'
     show FastaMessage, codeExpectedButGot, codeExpectedFunctionBody;
 
 import '../parser/parser.dart' show FormalParameterType, MemberKind, optional;
 
 import '../parser/identifier_context.dart' show IdentifierContext;
 
 import 'package:front_end/src/fasta/kernel/kernel_shadow_ast.dart';
 
 import 'package:front_end/src/fasta/kernel/utils.dart' show offsetForToken;
 
-import 'package:front_end/src/fasta/type_inference/type_inference_engine.dart'
-    show FieldNode;
-
 import 'package:front_end/src/fasta/type_inference/type_inferrer.dart'
     show TypeInferrer;
 
 import 'package:front_end/src/fasta/type_inference/type_promotion.dart'
     show TypePromoter;
 
 import 'package:kernel/ast.dart';
 
 import 'package:kernel/clone.dart' show CloneVisitor;
 
@@ skipping 56 matching lines @@
   final bool enableNative;
 
   @override
   final Uri uri;
 
   final TypeInferrer _typeInferrer;
 
   @override
   final TypePromoter<Expression, VariableDeclaration> typePromoter;
 
-  /// If not `null`, dependencies on fields are accumulated into this list.
-  ///
-  /// If `null`, no dependency information is recorded.
-  final List<FieldNode> fieldDependencies;
-
   /// Only used when [member] is a constructor. It tracks if an implicit super
   /// initializer is needed.
   ///
   /// An implicit super initializer isn't needed
   ///
   /// 1. if the current class is Object,
   /// 2. if there is an explicit super initializer,
   /// 3. if there is a redirecting (this) initializer, or
   /// 4. if a compile-time error prevented us from generating code for an
   ///    initializer. This avoids cascading errors.
@@ skipping 28 matching lines @@
   BodyBuilder(
       KernelLibraryBuilder library,
       this.member,
       Scope scope,
       this.formalParameterScope,
       this.hierarchy,
       this.coreTypes,
       this.classBuilder,
       this.isInstanceMember,
       this.uri,
-      this._typeInferrer,
-      {this.fieldDependencies})
+      this._typeInferrer)
       : enclosingScope = scope,
         library = library,
         enableNative = (library.uri.scheme == "dart" || library.isPatch),
         needsImplicitSuperInitializer =
             coreTypes.objectClass != classBuilder?.cls,
         typePromoter = _typeInferrer.typePromoter,
         super(scope);
 
   bool get hasParserError => recoverableErrors.isNotEmpty;
 
@@ skipping 2611 matching lines @@
         fileUri: message.uri);
   }
 
   @override
   void debugEvent(String name) {
     // printEvent(name);
   }
 
   @override
   StaticGet makeStaticGet(Member readTarget, Token token) {
-    // TODO(paulberry): only record the dependencies mandated by the top level
-    // type inference spec.
-    if (fieldDependencies != null && readTarget is KernelField) {
-      var fieldNode = _typeInferrer.getFieldNodeForReadTarget(readTarget);
-      if (fieldNode != null) {
-        fieldDependencies.add(fieldNode);
-      }
-    }
     return new KernelStaticGet(readTarget)..fileOffset = offsetForToken(token);
   }
 }
 
 class Identifier {
   final Token token;
   String get name => token.lexeme;
 
   Identifier(this.token);
 
@@ skipping 440 matching lines @@
     if (starToken == null) {
       return AsyncMarker.Async;
     } else {
       assert(identical(starToken.stringValue, "*"));
       return AsyncMarker.AsyncStar;
     }
   } else {
     return internalError("Unknown async modifier: $asyncToken");
   }
 }