Assert that we don't mix K and J elements

tests/compiler/dart2js/equivalence/check_functions.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.
 
 /// Equivalence test functions for data objects.
 
 library dart2js.equivalence.functions;
 
 import 'package:expect/expect.dart';
 import 'package:compiler/src/common/resolution.dart';
@@ skipping 346 matching lines @@
 void checkNativeClasses(
     Compiler compiler1, Compiler compiler2, TestStrategy strategy) {
   Iterable<ClassEntity> nativeClasses1 = compiler1
       .backend.nativeResolutionEnqueuerForTesting.nativeClassesForTesting;
   Iterable<ClassEntity> nativeClasses2 = compiler2
       .backend.nativeResolutionEnqueuerForTesting.nativeClassesForTesting;
 
   checkSetEquivalence(compiler1, compiler2, 'nativeClasses', nativeClasses1,
       nativeClasses2, strategy.elementEquivalence);
 
-  Iterable<ClassEntity> registeredClasses1 = compiler1
-      .backend.nativeResolutionEnqueuerForTesting.registeredClassesForTesting;
-  Iterable<ClassEntity> registeredClasses2 = compiler2
-      .backend.nativeResolutionEnqueuerForTesting.registeredClassesForTesting;
+  Iterable<ClassEntity> liveNativeClasses1 =
+      compiler1.backend.nativeResolutionEnqueuerForTesting.liveNativeClasses;
+  Iterable<ClassEntity> liveNativeClasses2 =
+      compiler2.backend.nativeResolutionEnqueuerForTesting.liveNativeClasses;
 
-  checkSetEquivalence(compiler1, compiler2, 'registeredClasses',
-      registeredClasses1, registeredClasses2, strategy.elementEquivalence);
+  checkSetEquivalence(compiler1, compiler2, 'liveNativeClasses',
+      liveNativeClasses1, liveNativeClasses2, strategy.elementEquivalence);
 }
 
 void checkNativeBasicData(NativeBasicDataImpl data1, NativeBasicDataImpl data2,
     TestStrategy strategy) {
   checkMapEquivalence(
       data1,
       data2,
       'nativeClassTagInfo',
       data1.nativeClassTagInfo,
       data2.nativeClassTagInfo,
@@ skipping 1024 matching lines @@
     return testNodes(node.expression, other.expression);
   }
 
   @override
   bool visitBlock(js.Block node) {
     if (peek() is! js.Block) return failAt(node, peek());
     js.Block other = peek();
     return testNodeLists(node.statements, other.statements);
   }
 }