Re-apply change to move to plugin package

pkg/analyzer/test/plugin/test_all.dart

Index: pkg/analyzer/test/plugin/test_all.dart
diff --git a/pkg/analyzer/test/plugin/test_all.dart b/pkg/analyzer/test/plugin/test_all.dart
deleted file mode 100644
index e8b0ce35f217eeceb43cd8bea85a5115d6a9df11..0000000000000000000000000000000000000000
--- a/pkg/analyzer/test/plugin/test_all.dart
+++ /dev/null
@@ -1,19 +0,0 @@
-// Copyright (c) 2015, 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 test.plugin.all;
-
-import 'package:unittest/unittest.dart';
-
-import 'plugin_impl_test.dart' as plugin_impl;
-
-/**
- * Utility for manually running all tests.
- */
-main() {
-  groupSep = ' | ';
-  group('plugins', () {
-    plugin_impl.main();
-  });
-}