anchor.diff:  import 'package:angular2/src/compiler/config.dart';
   import 'package:angular2/src/transform/common/asset_reader.dart';
   import 'package:angular2/src/compiler/source_module.dart';
  +import 'package:angular2/src/source_gen/common/url_resolver.dart';
   import 'package:angular2/src/transform/common/logging.dart';
   import 'package:angular2/src/transform/common/names.dart';
   import 'package:angular2/src/transform/common/options.dart';
   import 'package:angular2/src/transform/common/ng_compiler.dart';
  -import 'package:angular2/src/transform/common/url_resolver.dart';
   import 'package:angular2/src/transform/common/zone.dart' as zone;
   import 'package:analyzer/dart/ast/token.dart' show Keyword;
   import 'package:barback/barback.dart';
  +import 'package:build/build.dart' as build;
  +
  +/// Converts a Barback asset ID to an asset URL.
  +String _assetIdToUrl(AssetId assetId) {
  +  final buildAssetId = new build.AssetId(assetId.package, assetId.path);
  +  return toAssetUri(buildAssetId);
  +}
  +
  +/// Converts an asset URL to a Barback asset ID.
  +AssetId _urlToAssetId(String url) {
  +  final buildAssetId = new build.AssetId.resolve(url);
  +  return new AssetId(buildAssetId.package, buildAssetId.path);
  +}
   
   AssetId shimmedStylesheetAssetId(AssetId cssAssetId) => new AssetId(
       cssAssetId.package, toShimmedStylesheetExtension(cssAssetId.path));
  
positive.code: 
  Future<Iterable<Asset>> processStylesheet(AssetReader reader,
      AssetId stylesheetId, TransformerOptions options) async {
    final stylesheetUrl = toAssetUri(stylesheetId);
    var templateCompiler = zone.templateCompiler;
    if (templateCompiler == null) {
      var config = new CompilerConfig(
  
negative.code:         templateCompiler.compileStylesheet(stylesheetUrl, cssText);
  
      return sourceModules.map((SourceModule module) => new Asset.fromString(
          _urlToAssetId(module.moduleUrl), writeSourceModule(module)));
    }, operationName: 'processStylesheet', assetId: stylesheetId);
  }
  
  