Start pulling pub from its own repo.

sdk/lib/_internal/pub/test/run/nonexistent_script_test.dart

Index: sdk/lib/_internal/pub/test/run/nonexistent_script_test.dart
diff --git a/sdk/lib/_internal/pub/test/run/nonexistent_script_test.dart b/sdk/lib/_internal/pub/test/run/nonexistent_script_test.dart
deleted file mode 100644
index 7704fdf6ba4cd7cc37d5354796582940b7c4d15c..0000000000000000000000000000000000000000
--- a/sdk/lib/_internal/pub/test/run/nonexistent_script_test.dart
+++ /dev/null
@@ -1,22 +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.
-
-import 'package:path/path.dart' as p;
-
-import '../../lib/src/exit_codes.dart' as exit_codes;
-import '../descriptor.dart' as d;
-import '../test_pub.dart';
-
-main() {
-  initConfig();
-  integration('Errors if the script does not exist.', () {
-    d.dir(appPath, [
-      d.appPubspec()
-    ]).create();
-
-    var pub = pubRun(args: [p.join("bin", "script")]);
-    pub.stderr.expect("Could not find ${p.join("bin", "script.dart")}.");
-    pub.shouldExit(exit_codes.NO_INPUT);
-  });
-}