Adding JRecord and boxing mechanics.

pkg/compiler/lib/src/kernel/element_map_impl.dart

 // Copyright (c) 2017, 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 dart2js.kernel.element_map;
 
 import 'package:kernel/ast.dart' as ir;
 
 import '../closure.dart' show BoxLocal, ThisLocal;
 import '../common.dart';
@@ skipping 2232 matching lines @@
       Map<String, MemberEntity> memberMap,
       ir.VariableDeclaration variable,
       int fieldNumber,
       NodeBox box,
       KernelToLocalsMap localsMap) {
     // NOTE: This construction order may be slightly different than the
     // old Element version. The old version did all the boxed items and then
     // all the others.
     Local capturedLocal = localsMap.getLocalVariable(variable);
     if (cls.isBoxed(capturedLocal)) {
-      FieldEntity boxedField = new JBoxedField(
+      FieldEntity boxedField = new JRecord(
           _getClosureVariableName(capturedLocal.name, fieldNumber),
           _memberData.length,
           new BoxLocal(box.name,
               localsMap.getLocalVariable(box.executableContext), member),
           cls.closureClassEntity,
-          variable.isConst,
-          variable.isFinal || variable.isConst);
+          variable.isConst);
       cls.localToFieldMap[capturedLocal] = boxedField;
       _memberList.add(boxedField);
       _memberData.add(new ClosureFieldData(new ClosureMemberDefinition(
           boxedField,
           computeSourceSpanFromTreeNode(variable),
           MemberKind.closureField,
           variable)));
       memberMap[boxedField.name] = boxedField;
     } else {
       FieldEntity closureField = new JClosureField(
@@ skipping 61 matching lines @@
   ///
   /// These names are not used in generated code, just as element name.
   String _getClosureVariableName(String name, int id) {
     return "_captured_${name}_$id";
   }
 
   String getDeferredUri(ir.LibraryDependency node) {
     throw new UnimplementedError('JsKernelToElementMap.getDeferredUri');
   }
 }