Support enums in dart2js.

pkg/compiler/lib/src/elements/elements.dart

 // Copyright (c) 2012, 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 elements;
 
 
 import '../constants/expressions.dart';
 import '../tree/tree.dart';
 import '../util/util.dart';
@@ skipping 1309 matching lines @@
   Link<Element> get constructors;
 
   ClassElement get patch;
   ClassElement get origin;
   ClassElement get declaration;
   ClassElement get implementation;
 
   int get supertypeLoadState;
   String get nativeTagInfo;
 
+  /// `true` if this class is an enum declaration.
+  bool get isEnumClass;
   bool get isMixinApplication;
   bool get isUnnamedMixinApplication;
   bool get hasBackendMembers;
   bool get hasLocalScopeMembers;
 
   /// Returns `true` if this class is `Object` from dart:core.
   bool get isObject;
 
   bool isSubclassOf(ClassElement cls);
   /// Returns true if `this` explicitly/nominally implements [intrface].
   ///
   /// Note that, if [intrface] is the `Function` class, this method returns
   /// falso for a class that has a `call` method but does not explicitly
   /// implement `Function`.
   bool implementsInterface(ClassElement intrface);
   bool hasFieldShadowedBy(Element fieldMember);
 
   /// Returns `true` if this class has a @proxy annotation.
   bool get isProxy;
 
   /// Returns `true` if the class hierarchy for this class contains errors.
   bool get hasIncompleteHierarchy;
 
   void addMember(Element element, DiagnosticListener listener);
   void addToScope(Element element, DiagnosticListener listener);
 
-  void setDefaultConstructor(FunctionElement constructor, Compiler compiler);
-
   void addBackendMember(Element element);
   void reverseBackendMembers();
 
   Element lookupMember(String memberName);
   Element lookupSelector(Selector selector);
   Element lookupSuperSelector(Selector selector);
 
   Element lookupLocalMember(String memberName);
   Element lookupBackendMember(String memberName);
   Element lookupSuperMember(String memberName);
@@ skipping 234 matching lines @@
   bool get isDeclaredByField;
 
   /// Returns `true` if this member is abstract.
   bool get isAbstract;
 
   /// If abstract, [implementation] points to the overridden concrete member,
   /// if any. Otherwise [implementation] points to the member itself.
   Member get implementation;
 }