Remove deprecated packages from the repo

pkg/custom_element/test/analyzer_test.dart

Index: pkg/custom_element/test/analyzer_test.dart
diff --git a/pkg/custom_element/test/analyzer_test.dart b/pkg/custom_element/test/analyzer_test.dart
deleted file mode 100644
index 0cbe6206bd57a6ae9f5cc2e92de9a406cf684a6c..0000000000000000000000000000000000000000
--- a/pkg/custom_element/test/analyzer_test.dart
+++ /dev/null
@@ -1,11 +0,0 @@
-// 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 custom_element.test.analyzer_test;
-
-import 'package:custom_element/custom_element.dart';
-
-// This test ensures CustomElement compiles without errors.
-void main() {
-}