Revise barback logging patch.

pkg/barback/lib/src/pool.dart

Index: pkg/barback/lib/src/pool.dart
diff --git a/pkg/barback/lib/src/pool.dart b/pkg/barback/lib/src/pool.dart
index 8da8434723a73289c9d945ff50ee249e55e20d4a..3224fbef80c4d82f7d2c7b9699293a58ee8e3670 100644
--- a/pkg/barback/lib/src/pool.dart
+++ b/pkg/barback/lib/src/pool.dart
@@ -1,3 +1,9 @@
+// Copyright (c) 2013, 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 barback.pool;
+
 import 'dart:async';
 import 'dart:collection';