Dart2js enum parsing.

sdk/lib/_internal/compiler/implementation/tree/unparser.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.
 
 part of tree;
 
 String unparse(Node node) {
   Unparser unparser = new Unparser();
   unparser.unparse(node);
   return unparser.result;
@@ skipping 55 matching lines @@
       sb.write(' ');
       visit(node.interfaces);
     }
     sb.write('{');
     for (final member in members) {
       visit(member);
     }
     sb.write('}');
   }
 
+  visitEnum(Enum node) {
+    sb.write('enum ');
+    visit(node.name);
+    sb.write(' ');
+    visit(node.names);
+  }
+
   visitClassNode(ClassNode node) {
     unparseClassWithBody(node, node.body.nodes);
   }
 
   visitMixinApplication(MixinApplication node) {
     visit(node.superclass);
     sb.write(' with ');
     visit(node.mixins);
   }
 
@@ skipping 531 matching lines @@
   }
 
   visitStatement(Statement node) {
     throw 'internal error'; // Should not be called.
   }
 
   visitStringNode(StringNode node) {
     throw 'internal error'; // Should not be called.
   }
 }