anchor.diff:    ..addOption('output-incremental-dill',
         help: 'Output path for the generated incremental dill',
         defaultsTo: null)
  +  ..addOption('depfile',
  +      help: 'Path to output Ninja depfile. Only used in batch mode.')
     ..addOption('packages',
         help: '.packages file to use for compilation',
         defaultsTo: null)
  
positive.code:             print: (Zone self, ZoneDelegate parent, Zone zone, String line) =>
                  _outputStream.writeln(line)));
    }
  }
  
  /// Entry point for this module, that creates `_FrontendCompiler` instance and
  
negative.code:       printer.writeProgramFile(program);
        await sink.close();
        _outputStream.writeln('$boundaryKey $_kernelBinaryFilename');
  
        final String depfile = options['depfile'];
        if (depfile != null) {
          await _writeDepfile(program, _kernelBinaryFilename, depfile);
        }
  
        _kernelBinaryFilename = _kernelBinaryFilenameIncremental;
      } else
        _outputStream.writeln(boundaryKey);
  