Serialize prefix members.

tests/compiler/dart2js/serialization/equivalence_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.serialization_test;
 
 import 'dart:io';
 import '../memory_compiler.dart';
 import 'package:async_helper/async_helper.dart';
 import 'package:compiler/src/commandline_options.dart';
@@ skipping 832 matching lines @@
     check(
         element1, element2, 'isDeferred',
         element1.isDeferred, element2.isDeferred);
     checkElementIdentities(
         element1, element2, 'deferredImport',
         element1.deferredImport, element2.deferredImport);
     if (element1.isDeferred) {
       checkElementProperties(element1, element2,
           'loadLibrary', element1.loadLibrary, element2.loadLibrary);
     }
-    // TODO(johnniwinther): Check members.
+    element1.forEachLocalMember((Element member1) {
+      String name = member1.name;
+      Element member2 = element2.lookupLocalMember(name);
+      checkElementIdentities(element1, element2, 'lookupLocalMember:$name',
+          member1, member2);
+    });
   }
 
   @override
   void visitErroneousElement(
       ErroneousElement element1, ErroneousElement element2) {
     check(element1, element2, 'messageKind',
         element1.messageKind, element2.messageKind);
   }
 }