Add ConstructorBodyEntity

tests/compiler/dart2js/kernel/test_helpers.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 dart2js.kernel.equivalence;
 
 import 'package:compiler/src/common/backend_api.dart';
 import 'package:compiler/src/common/resolution.dart';
 import 'package:compiler/src/common/work.dart';
 import 'package:compiler/src/constants/expressions.dart';
@@ skipping 43 matching lines @@
                   a, b, 'enclosingClass', a.enclosingClass, b.enclosingClass);
         }
         return false;
       case ElementKind.FACTORY_CONSTRUCTOR:
         if (b is KFactoryConstructor) {
           return strategy.test(a, b, 'name', a.name, b.name) &&
               strategy.testElements(
                   a, b, 'enclosingClass', a.enclosingClass, b.enclosingClass);
         }
         return false;
+      case ElementKind.GENERATIVE_CONSTRUCTOR_BODY:
+        ConstructorBodyElement aConstructorBody = a;
+        if (b is ConstructorBodyEntity) {
+          return entityEquivalence(aConstructorBody.constructor, b.constructor);
+        }
+        return false;
       case ElementKind.CLASS:
         if (b is KClass) {
           List<InterfaceType> aMixinTypes = [];
           List<InterfaceType> bMixinTypes = [];
           ClassElement aClass = a;
           if (aClass.isUnnamedMixinApplication) {
             if (!testing.isUnnamedMixinApplication(b)) {
               return false;
             }
             while (aClass.isMixinApplication) {
@@ skipping 224 matching lines @@
     for (ConstructorElement constructor in element.constructors) {
       if (!constructor.isRedirectingFactory) {
         return true;
       }
     }
     // The class cannot itself be instantiated.
     return false;
   }
   return true;
 }