Handle fields with initializers in constant constructors.

tests/compiler/dart2js/constant_expression_evaluate_test.dart

 // Copyright (c) 2015, 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.constants.expressions.evaluate_test;
 
 import 'dart:async';
 import 'package:async_helper/async_helper.dart';
 import 'package:expect/expect.dart';
 import 'package:compiler/src/constants/evaluation.dart';
@@ skipping 90 matching lines @@
 }
 class B {
   final field1;
   const B(this.field1);
 }
 class C extends B {
   final field2;
   const C({field1: 42, this.field2: false}) : super(field1);
   const C.named([field = false]) : this(field1: field, field2: field);
 }
+class D extends C {
+  final field3 = 99;
+  const D(a, b) : super(field2: a, field1: b);
+}
 ''', const [
     const ConstantData('const Object()',
         const { const {} : 'ConstructedConstant(Object())' }),
     const ConstantData('const A()',
         const { const {} : 'ConstructedConstant(A())' }),
     const ConstantData('const B(0)',
         const { const {} : 'ConstructedConstant(B(field1=IntConstant(0)))' }),
     const ConstantData('const B(const A())',
         const { const {} :
           'ConstructedConstant(B(field1=ConstructedConstant(A())))' }),
@@ skipping 12 matching lines @@
     const ConstantData('const C.named(87)', const { const {} :
         'ConstructedConstant(C(field1=IntConstant(87),'
                               'field2=IntConstant(87)))' }),
     const ConstantData('const C(field1: a, field2: b)', const {
         const {} :
           'ConstructedConstant(C(field1=BoolConstant(true),'
                                 'field2=IntConstant(42)))',
         const {'foo': 'false', 'bar': '87'} :
           'ConstructedConstant(C(field1=BoolConstant(false),'
                                 'field2=IntConstant(87)))', }),
+    const ConstantData('const D(42, 87)', const { const {} :
+       'ConstructedConstant(D(field1=IntConstant(87),'
+                             'field2=IntConstant(42),'
+                             'field3=IntConstant(99)))' }),
   ]),
   const TestData('''
 class A<T> implements B {
   final field1;
   const A({this.field1:42});
 }
 class B<S> implements C {
   const factory B({field1}) = A<B<S>>;
   const factory B.named() = A<S>;
 }
@@ skipping 76 matching lines @@
       Environment environment = new MemoryEnvironment(compiler, env);
       ConstantValue value =
           constant.evaluate(environment, DART_CONSTANT_SYSTEM);
       String valueText = value.toStructuredText();
       Expect.equals(expectedText, valueText,
           "Unexpected value '${valueText}' for contant "
           "`${constant.toDartText()}`, expected '${expectedText}'.");
     });
   });
 }