Added .scss transform

pkg/polymer/lib/src/transform.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.
 
 /** Transfomers used for pub-serve and pub-deploy. */
 // TODO(sigmund): move into a plugin directory when pub supports it.
 library polymer.src.transform;
 
 import 'package:observe/transform.dart';
+import 'package:csslib/transform.dart';
 import 'transform/code_extractor.dart';
 import 'transform/import_inliner.dart';
 import 'transform/script_compactor.dart';
 import 'transform/polyfill_injector.dart';
 
 export 'transform/code_extractor.dart';
 export 'transform/import_inliner.dart';
 export 'transform/script_compactor.dart';
 export 'transform/polyfill_injector.dart';
 
 /** Phases to deploy a polymer application. */
 var phases = [
   [new InlineCodeExtractor()],
   [new ObservableTransformer()],
+  [new ScssTransformer()],

[Siggi Cherem (dart-lang), 2013/09/08 20:31:33]

we should be able to run this in parallel with other phases. So maybe add it to
the same list as Observable?

(I'm thinking that eventually the code-extractor will extract the .css from the
html

   [new ImportedElementInliner()],
   [new ScriptCompactor()],
   [new PolyfillInjector()]
 ];