Remove barback from the repo.

pkg/barback/test/transformer/log.dart

-// 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.test.transformer.log;
-
-import 'dart:async';
-
-import 'package:barback/barback.dart';
-import 'package:barback/src/utils.dart';
-
-import 'mock.dart';
-
-/// A transformer that logs given entries during its apply.
-class LogTransformer extends MockTransformer {
-  /// The list of entries that it should log.
-  ///
-  /// Each entry has the log level followed by the message, like:
-  ///
-  ///     error: This is the error message.
-  final List<String> _entries;
-
-  LogTransformer(this._entries);
-
-  bool doIsPrimary(AssetId id) => true;
-
-  void doApply(Transform transform) {
-    for (var entry in _entries) {
-      var parts = entry.split(":");
-      var logFn;
-      switch (parts[0]) {
-        case "error":   logFn = transform.logger.error; break;
-        case "warning": logFn = transform.logger.warning; break;
-        case "info":    logFn = transform.logger.info; break;
-        case "fine":    logFn = transform.logger.fine; break;
-      }
-
-      logFn(parts[1].trim());
-    }
-  }
-}