anchor.diff:  const String _kOptionAsset = 'asset-dir';
   const String _kOptionManifest = 'manifest';
   const String _kOptionAssetManifestOut = 'asset-manifest-out';
  +const String _kOptionComponentName = 'component-name';
   const List<String> _kRequiredOptions = <String>[
     _kOptionPackages,
     _kOptionAsset,
  
positive.code: 
    for (String path in assets.entries.keys) {
      outFile.write('data/$path=$outputBase/$path\n');
    }
    await outFile.flush();
    await outFile.close();
  
negative.code:   await Future.wait(calls);
  
    final String outputMan = argResults[_kOptionAssetManifestOut];
    await writeFuchsiaManifest(assets, argResults[_kOptionAsset], outputMan, argResults[_kOptionComponentName]);
  }
  
  Future<Null> writeFuchsiaManifest(AssetBundle assets, String outputBase, String fileDest, String componentName) async {
  
    final libfs.File destFile = libfs.fs.file(fileDest);
    await destFile.create(recursive: true);
  