anchor.diff:        _removePackagesLinks(context, entity);
       }
     });
  -}
  -
  -/**
  - * Remove a Dartium only reference to the dart:nativewrappers library. dart2js
  - * will not be able to compile code with these references.
  - */
  -void _removeNativeWrappersReference(
  -    GrinderContext context, Directory dir, String fileName) {
  -  File file = joinFile(dir, [fileName]);
  -  String contents = file.readAsStringSync();
  -  String modified = _replaceNativeWrappersReference(context, contents);
  -  if (modified == contents) {
  -    context.log('No reference to dart:nativewrappers found!');
  -  } else {
  -    context.log('Removing reference to dart:nativewrappers.');
  -    file.writeAsStringSync(modified);
  -  }
  -}
  -
  -String _replaceNativeWrappersReference(GrinderContext context, String contents) {
  -  // Look for `import 'dart:nativewrappers' as smoke_6;`.
  -  String importPrefix;
  -
  -  List<String> lines = contents.split('\n');
  -
  -  for (String line in lines) {
  -    if (line.contains("import 'dart:nativewrappers' as")) {
  -      // Remove the trailing semi-colon.
  -      line = line.substring(1, line.length - 1);
  -
  -      // Remove everything preceeding the import prefix - the ` as ` and
  -      // everything before it.
  -      importPrefix = line.substring(line.lastIndexOf(' ') + 1);
  -
  -      break;
  -    }
  -  }
  -
  -  // Couldn't find the import prefix...
  -  if (importPrefix == null) return contents;
  -
  -  context.log('Found dart:nativewrappers prefix: ${importPrefix}.');
  -
  -  // Remove lines that contain `importPrefix;` or `importPrefix.` and return the
  -  // modified content.
  -  return lines.map((String line) {
  -    if (line.contains('${importPrefix}.')) {
  -      // Remove any line that uses the import prefix.
  -      return '// ${line}';
  -    } else if (line.contains('${importPrefix};')) {
  -      // Remove the line declaring the import prefix.
  -      return '// ${line}';
  -    } else {
  -      return line;
  -    }
  -  }).join('\n');
   }
   
   /**
  
positive.code: 
    var sep = Platform.pathSeparator;
    _runCommandSync(
      context,
      'git checkout app${sep}manifest.json');
    _increaseBuildNumber(context);
    _runCommandSync(
      context,
      'git commit -m "Build version ${version}" app${sep}manifest.json');
  
    context.log('Created ${filename}');
    context.log('** A commit has been created, you need to push it. ***');
  
negative.code:       arguments: args,
        packageRoot: 'packages',
        workingDirectory: sourceDir.path);
  
    // Create an empty `user.json` overrides file so we don't get an error in the
    // console in the deployed application.
    File userJsonFile = joinFile(destDir, ['web', 'user.json']);
    if (!userJsonFile.existsSync()) {
      userJsonFile.writeAsStringSync('{}\n');
    }
  }
  
  void _dart2jsCompile(GrinderContext context, Directory target, String filePath,
  