Merge CoreTypes and CoreClasses into CommonElements.

tests/compiler/dart2js/mirrors_used_test.dart

 // Copyright (c) 2013, 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.
 
 /// Test that the @MirrorsUsed annotation suppress hints and that only
 /// requested elements are retained for reflection.
 library dart2js.test.mirrors_used_test;
 
 import 'package:expect/expect.dart';
 import "package:async_helper/async_helper.dart";
@@ skipping 66 matching lines @@
     ]; // The (getter) name of Foo.field.
     // TODO(ahe): Check for the following names, currently they are not being
     // recorded correctly, but are being emitted.
     [
       'Foo_staticMethod', // The name of Foo.staticMethod.
       r'instanceMethod$0'
     ]; // The name of Foo.instanceMethod.
 
     // We always include the names of some native classes.
     List<Element> nativeClasses = [
-      compiler.coreClasses.intClass,
-      compiler.coreClasses.doubleClass,
-      compiler.coreClasses.numClass,
-      compiler.coreClasses.stringClass,
-      compiler.coreClasses.boolClass,
-      compiler.coreClasses.nullClass,
-      compiler.coreClasses.listClass
+      compiler.commonElements.intClass,
+      compiler.commonElements.doubleClass,
+      compiler.commonElements.numClass,
+      compiler.commonElements.stringClass,
+      compiler.commonElements.boolClass,
+      compiler.commonElements.nullClass,
+      compiler.commonElements.listClass
     ];
     JavaScriptBackend backend = compiler.backend;
     Iterable<String> nativeNames = nativeClasses.map(backend.namer.className);
     expectedNames = expectedNames.map(backend.namer.asName).toList();
     expectedNames.addAll(nativeNames);
 
     // Mirrors only work in the full emitter. We can thus be certain that the
     // emitter is the full emitter.
     full.Emitter fullEmitter = backend.emitter.emitter;
     Set recordedNames = new Set()
@@ skipping 76 matching lines @@
 library lib;
 
 import 'dart:mirrors';
 
 useReflect(type) {
   print(new Symbol('Foo'));
   print(MirrorSystem.getName(reflectClass(type).owner.qualifiedName));
 }
 """,
 };