move delete_file and remove_sourcemap_comment transformers to code_transformers

pkg/code_transformers/test/remove_sourcemap_comment_test.dart

Index: pkg/code_transformers/test/remove_sourcemap_comment_test.dart
diff --git a/pkg/polymer/test/build/remove_sourcemap_comment_test.dart b/pkg/code_transformers/test/remove_sourcemap_comment_test.dart
similarity index 79%
copy from pkg/polymer/test/build/remove_sourcemap_comment_test.dart
copy to pkg/code_transformers/test/remove_sourcemap_comment_test.dart
index 44d1f455b4d7e3142379669bebcdddef0c8f7b79..6a9720d13c2d4e03dc91c1ad8c47d5bb025290ac 100644
--- a/pkg/polymer/test/build/remove_sourcemap_comment_test.dart
+++ b/pkg/code_transformers/test/remove_sourcemap_comment_test.dart
@@ -2,13 +2,13 @@
 // 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 polymer.test.build.remove_sourcemap_comment_test;
+library code_transformers.test.remove_sourcemap_comment_test;
 
 import 'package:barback/barback.dart';
-import 'package:polymer/src/build/remove_sourcemap_comment.dart';
+import 'package:code_transformers/src/remove_sourcemap_comment.dart';
+import 'package:code_transformers/tests.dart';
 import 'package:unittest/compact_vm_config.dart';
 import 'package:unittest/unittest.dart';
-import 'common.dart';
 
 final phases = [[new RemoveSourcemapComment.asPlugin(
     new BarbackSettings({}, BarbackMode.RELEASE))]];