Fix an interface error in the polymer transformer.

pkg/polymer/lib/transformer.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.
 
 /** Transfomer used for pub-serve and pub-deploy. */
 library polymer.transformer;
 
 import 'package:barback/barback.dart';
 import 'package:observe/transform.dart';
 import 'src/build/code_extractor.dart';
@@ skipping 36 matching lines @@
       entryPoints = [value];
       error = false;
     } else {
       error = true;
     }
 
     if (error) {
       print('Invalid value for "entry_points" in the polymer transformer.');
     }
   }
-  return new TransformOptions(entryPoints);
+  return new TransformOptions(entryPoints: entryPoints);
 }
 
 List<List<Transformer>> _createDeployPhases(TransformOptions options) {
   return [
     [new InlineCodeExtractor(options)],
     [new ObservableTransformer()],
     [new ImportInliner(options)],
     [new ScriptCompactor(options)],
     [new PolyfillInjector(options)]
   ];
 }