Add a "pub global run" command.

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

-// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS d.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:scheduled_test/scheduled_process.dart';
-import 'package:scheduled_test/scheduled_test.dart';
-
-import '../test_pub.dart';
-
-/// Schedules starting the "pub run" process and validates the expected startup
-/// output.
-///
-/// if [transformers] is given, it should contain a list of transformer IDs
-/// (like "myapp/src/transformer") and this will validate that the output for
-/// loading those is shown.
-///
-/// Returns the `pub run` process.
-ScheduledProcess pubRun({Iterable<String> args,
-  Iterable<String> transformers}) {
-  var pub = startPub(args: ["run"]..addAll(args));
-
-  // This isn't normally printed, but the pub test infrastructure runs pub in
-  // verbose mode, which enables this.
-  pub.stdout.expect(startsWith("Loading source assets"));
-
-  if (transformers != null) {
-    for (var transformer in transformers) {
-      pub.stdout.expect(startsWith("Loading $transformer transformers"));
-    }
-  }
-  return pub;
-}