Pull args, intl, logging, shelf, and source_maps out of the SDK.

pkg/args/lib/src/usage_exception.dart

Index: pkg/args/lib/src/usage_exception.dart
diff --git a/pkg/args/lib/src/usage_exception.dart b/pkg/args/lib/src/usage_exception.dart
deleted file mode 100644
index 35cc7442e549b93da0e825ae660171c7361c3647..0000000000000000000000000000000000000000
--- a/pkg/args/lib/src/usage_exception.dart
+++ /dev/null
@@ -1,14 +0,0 @@
-// 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 args.usage_exception;
-
-class UsageException implements Exception {
-  final String message;
-  final String usage;
-
-  UsageException(this.message, this.usage);
-
-  String toString() => "$message\n\n$usage";
-}