Restructure the yaml package.

pkg/yaml/lib/src/yaml_exception.dart

Index: pkg/yaml/lib/src/yaml_exception.dart
diff --git a/samples/tests/samples/browser/swipe_test.dart b/pkg/yaml/lib/src/yaml_exception.dart
similarity index 54%
copy from samples/tests/samples/browser/swipe_test.dart
copy to pkg/yaml/lib/src/yaml_exception.dart
index c85894143752b113b60e8b40e0d923a029ffe752..66697a18eeb5d59be7dd633391d698fad8573d22 100644
--- a/samples/tests/samples/browser/swipe_test.dart
+++ b/pkg/yaml/lib/src/yaml_exception.dart
@@ -2,16 +2,14 @@
 // 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 swipe_test;
+library yaml_exception;
 
-import '../../../swipe/web/swipe.dart' as swipe;
+/// An error thrown by the YAML processor.
+class YamlException implements Exception {
+  final String _msg;
 
-// @static-clean
+  YamlException(this._msg);
 
-/**
- * This test exists to ensure that the swipe sample compiles without errors.
- */
-void main() {
-  
+  String toString() => _msg;
 }