Deprecate internal packages (#1054)

Mark internal packages as deprecated to hopefully prevent accidental use.
diff --git a/pkgs/test/CHANGELOG.md b/pkgs/test/CHANGELOG.md
index e8a7521..a0e29f8 100644
--- a/pkgs/test/CHANGELOG.md
+++ b/pkgs/test/CHANGELOG.md
@@ -1,4 +1,9 @@
+## 1.6.8
+
+* Depend on the latest `test_core` and `test_api`.
+
 ## 1.6.7
+
 * Allow `analyzer` version `0.38.x`.
 
 ## 1.6.6
diff --git a/pkgs/test/lib/test.dart b/pkgs/test/lib/test.dart
index 179604c..961dae1 100644
--- a/pkgs/test/lib/test.dart
+++ b/pkgs/test/lib/test.dart
@@ -2,4 +2,5 @@
 // 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.
 
+// ignore: deprecated_member_use
 export 'package:test_core/test_core.dart';
diff --git a/pkgs/test/pubspec.yaml b/pkgs/test/pubspec.yaml
index d959265..10bf8d1 100644
--- a/pkgs/test/pubspec.yaml
+++ b/pkgs/test/pubspec.yaml
@@ -1,5 +1,5 @@
 name: test
-version: 1.6.7-dev
+version: 1.6.8
 author: Dart Team <misc@dartlang.org>
 description: A full featured library for writing and running Dart tests.
 homepage: https://github.com/dart-lang/test/blob/master/pkgs/test
@@ -31,8 +31,8 @@
   web_socket_channel: ^1.0.0
   yaml: ^2.0.0
   # Use an exact version until the test_api and test_core package are stable.
-  test_api: 0.2.6
-  test_core: 0.2.8
+  test_api: 0.2.7
+  test_core: 0.2.9
 
 dev_dependencies:
   fake_async: ^1.0.0
@@ -40,3 +40,8 @@
   test_descriptor: ^1.0.0
   test_process: ^1.0.0
 
+dependency_overrides:
+  test_api:
+    path: ../test_api
+  test_core:
+    path: ../test_core
diff --git a/pkgs/test_api/CHANGELOG.md b/pkgs/test_api/CHANGELOG.md
index 317d49d..f3cb847 100644
--- a/pkgs/test_api/CHANGELOG.md
+++ b/pkgs/test_api/CHANGELOG.md
@@ -1,6 +1,7 @@
 ## 0.2.7
 
 * Prepare for upcoming `Stream<List<int>>` changes in the Dart SDK.
+* Mark `package:test_api` as deprecated to prevent accidental use.
 
 ## 0.2.6
 
diff --git a/pkgs/test_api/lib/backend.dart b/pkgs/test_api/lib/backend.dart
index be30cf9..9fb8ac1 100644
--- a/pkgs/test_api/lib/backend.dart
+++ b/pkgs/test_api/lib/backend.dart
@@ -2,6 +2,10 @@
 // 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.
 
+@Deprecated('package:test_api is not intended for general use. '
+    'Please use package:test.')
+library test_api.backend;
+
 export 'src/backend/metadata.dart' show Metadata;
 export 'src/backend/platform_selector.dart' show PlatformSelector;
 export 'src/backend/runtime.dart' show Runtime;
diff --git a/pkgs/test_api/lib/test_api.dart b/pkgs/test_api/lib/test_api.dart
index 40c3f2b..9fab4e1 100644
--- a/pkgs/test_api/lib/test_api.dart
+++ b/pkgs/test_api/lib/test_api.dart
@@ -2,6 +2,10 @@
 // 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.
 
+@Deprecated('package:test_api is not intended for general use. '
+    'Please use package:test.')
+library test_api;
+
 import 'dart:async';
 
 import 'package:meta/meta.dart';
@@ -15,8 +19,8 @@
 export 'src/frontend/expect.dart' hide formatFailure;
 export 'src/frontend/expect_async.dart';
 export 'src/frontend/future_matchers.dart';
-export 'src/frontend/on_platform.dart';
 export 'src/frontend/never_called.dart';
+export 'src/frontend/on_platform.dart';
 export 'src/frontend/prints_matcher.dart';
 export 'src/frontend/retry.dart';
 export 'src/frontend/skip.dart';
diff --git a/pkgs/test_core/CHANGELOG.md b/pkgs/test_core/CHANGELOG.md
index 12c324c..3c690e1 100644
--- a/pkgs/test_core/CHANGELOG.md
+++ b/pkgs/test_core/CHANGELOG.md
@@ -1,3 +1,8 @@
+## 0.2.9
+
+* Mark `package:test_core` as deprecated to prevent accidental use.
+* Depend on the latest `test_api`.
+
 ## 0.2.8
 
 * Depend on `vm_service` instead of `vm_service_lib`.
diff --git a/pkgs/test_core/lib/backend.dart b/pkgs/test_core/lib/backend.dart
index 3d7ef67..afc15e9 100644
--- a/pkgs/test_core/lib/backend.dart
+++ b/pkgs/test_core/lib/backend.dart
@@ -2,6 +2,11 @@
 // 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.
 
+@Deprecated('package:test_core is not intended for general use. '
+    'Please use package:test.')
+library test_core.backend;
+
+//ignore: deprecated_member_use
 export 'package:test_api/backend.dart'
     show Metadata, PlatformSelector, Runtime, SuitePlatform;
 
diff --git a/pkgs/test_core/lib/test_core.dart b/pkgs/test_core/lib/test_core.dart
index 2d81ab3..bcf3145 100644
--- a/pkgs/test_core/lib/test_core.dart
+++ b/pkgs/test_core/lib/test_core.dart
@@ -2,29 +2,32 @@
 // 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.
 
+@Deprecated('package:test_core is not intended for general use. '
+    'Please use package:test.')
+library test_core;
+
 import 'dart:async';
 
 import 'package:meta/meta.dart';
-
-export 'package:matcher/matcher.dart';
 import 'package:path/path.dart' as p;
 import 'package:pedantic/pedantic.dart';
-
-import 'package:test_api/backend.dart';
+import 'package:test_api/backend.dart'; //ignore: deprecated_member_use
+import 'package:test_api/src/backend/declarer.dart'; // ignore: implementation_imports
 import 'package:test_api/src/backend/invoker.dart'; // ignore: implementation_imports
 import 'package:test_api/src/frontend/timeout.dart'; // ignore: implementation_imports
-import 'package:test_api/src/backend/declarer.dart'; // ignore: implementation_imports
 import 'package:test_api/src/utils.dart'; // ignore: implementation_imports
 
 import 'src/runner/engine.dart';
-import 'src/runner/reporter/expanded.dart';
 import 'src/runner/plugin/environment.dart';
+import 'src/runner/reporter/expanded.dart';
 import 'src/runner/runner_suite.dart';
 import 'src/runner/suite.dart';
 
+export 'package:matcher/matcher.dart';
 // Hide implementations which don't support being run directly.
 // This file is an almost direct copy of import below, but with the global
 // declarer added.
+//ignore: deprecated_member_use
 export 'package:test_api/test_api.dart'
     hide test, group, setUp, setUpAll, tearDown, tearDownAll;
 
diff --git a/pkgs/test_core/pubspec.yaml b/pkgs/test_core/pubspec.yaml
index 486d842..35407a3 100644
--- a/pkgs/test_core/pubspec.yaml
+++ b/pkgs/test_core/pubspec.yaml
@@ -1,5 +1,5 @@
 name: test_core
-version: 0.2.8
+version: 0.2.9
 author: Dart Team <misc@dartlang.org>
 description: A basic library for writing tests and running them on the VM.
 homepage: https://github.com/dart-lang/test/blob/master/pkgs/test_core
@@ -31,4 +31,8 @@
   # properly constrains all features it provides.
   matcher: ">=0.12.5 <0.12.6"
   # Use an exact version until the test_api package is stable.
-  test_api: 0.2.6
+  test_api: 0.2.7
+
+dependency_overrides:
+  test_api:
+    path: ../test_api