Merge CoreTypes and CoreClasses into CommonElements.

tests/compiler/dart2js/serialization/model_test_helper.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.serialization_model_test;
 
 import 'dart:async';
 import 'dart:io';
 import 'package:async_helper/async_helper.dart';
 import 'package:expect/expect.dart';
@@ skipping 144 matching lines @@
       "JavaScriptBackend.hasRuntimeTypeSupport mismatch");
   Expect.equals(backend1.hasIsolateSupport, backend2.hasIsolateSupport,
       "JavaScriptBackend.hasIsolateSupport mismatch");
 }
 
 void checkClosedWorlds(ClosedWorld closedWorld1, ClosedWorld closedWorld2,
     {bool verbose: false}) {
   checkClassHierarchyNodes(
       closedWorld1,
       closedWorld2,
-      closedWorld1.getClassHierarchyNode(closedWorld1.coreClasses.objectClass),
-      closedWorld2.getClassHierarchyNode(closedWorld2.coreClasses.objectClass),
+      closedWorld1
+          .getClassHierarchyNode(closedWorld1.commonElements.objectClass),
+      closedWorld2
+          .getClassHierarchyNode(closedWorld2.commonElements.objectClass),
       verbose: verbose);
 }
 
 void checkBackendInfo(Compiler compilerNormal, Compiler compilerDeserialized,
     {bool verbose: false}) {
   checkSets(
       compilerNormal.enqueuer.resolution.processedEntities,
       compilerDeserialized.enqueuer.resolution.processedEntities,
       "Processed element mismatch",
       areElementsEquivalent, onSameElement: (a, b) {
@@ skipping 150 matching lines @@
         checkClassHierarchyNodes(closedWorld1, closedWorld2, child, other,
             verbose: verbose);
         found = true;
         break;
       }
     }
     if (!found) {
       if (child.isInstantiated) {
         print('Missing subclass ${child.cls} of ${node1.cls} '
             'in ${node2.directSubclasses}');
-        print(closedWorld1
-            .dump(verbose ? closedWorld1.coreClasses.objectClass : node1.cls));
-        print(closedWorld2
-            .dump(verbose ? closedWorld2.coreClasses.objectClass : node2.cls));
+        print(closedWorld1.dump(
+            verbose ? closedWorld1.commonElements.objectClass : node1.cls));
+        print(closedWorld2.dump(
+            verbose ? closedWorld2.commonElements.objectClass : node2.cls));
       }
       Expect.isFalse(
           child.isInstantiated,
           'Missing subclass ${child.cls} of ${node1.cls} in '
           '${node2.directSubclasses}');
     }
   }
   checkMixinUses(closedWorld1, closedWorld2, node1.cls, node2.cls,
       verbose: verbose);
 }
@@ skipping 83 matching lines @@
           a, b, (a, b) => areInstancesEquivalent(a, b, typeEquivalence)));
   return true;
 }
 
 bool areInstancesEquivalent(Instance instance1, Instance instance2,
     bool typeEquivalence(DartType a, DartType b)) {
   return typeEquivalence(instance1.type, instance2.type) &&
       instance1.kind == instance2.kind &&
       instance1.isRedirection == instance2.isRedirection;
 }