Get rid of all the library tags.

lib/src/asset/dart/serialize/aggregate_transform.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library pub.asset.serialize.aggregate_transform;
-
 import 'dart:async';
 import 'dart:isolate';
 
 import 'package:barback/barback.dart';
 // TODO(nweiz): don't import from "src" once issue 14966 is fixed.
 import 'package:barback/src/internal_asset.dart';
 
 import '../serialize.dart';
 import 'get_input_transform.dart';
 
@@ skipping 144 matching lines @@
             transform['primaryIds'], deserializeId),
         super(transform);
 
   void declareOutput(AssetId id) {
     call(_port, {
       'type': 'declareOutput',
       'output': serializeId(id)
     });
   }
 }