anchor.diff:      message.write(']');
       numMessages++;
       final attributes = {
  -      if (line == lines.length) 'num_chunks': numMessages.toString()
  +      if (line == lines.length) 'num_chunks': numMessages.toString(),
  +      if (buildbucketID != null) 'buildbucket_id': buildbucketID
       };
       var base64data = base64Encode(utf8.encode(message.toString()));
       var messageObject = {
  
positive.code:       help: 'Authorization token with a scope including pubsub publish.');
    parser.addOption('result_file',
        abbr: 'f', help: 'File containing the results to send');
  
    final options = parser.parse(args);
    if (options['help']) {
  
negative.code: 
    final lines = await File(options['result_file']).readAsLines();
    final token = await File(options['auth_token']).readAsString();
    final buildbucketID = options['id'];
    // Construct pubsub messages.
    var line = 0;
    var numMessages = 0;
  