Start pulling pub from its own repo.

sdk/lib/_internal/pub/test/cache/repair/empty_cache_test.dart

Index: sdk/lib/_internal/pub/test/cache/repair/empty_cache_test.dart
diff --git a/sdk/lib/_internal/pub/test/cache/repair/empty_cache_test.dart b/sdk/lib/_internal/pub/test/cache/repair/empty_cache_test.dart
deleted file mode 100644
index 9f398b7635f3a481c460620429cfe73db3282b6e..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub/test/cache/repair/empty_cache_test.dart
+++ /dev/null
@@ -1,16 +0,0 @@
-// Copyright (c) 2014, 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 pub_tests;
-
-import '../../test_pub.dart';
-
-main() {
-  initConfig();
-  integration('does nothing if the cache is empty', () {
-    // Repair them.
-    schedulePub(args: ["cache", "repair"],
-        output: "No packages in cache, so nothing to repair.");
-  });
-}