Run `pub get` with --verbose to debug flaky timeouts on pkg tests

tools/testing/dart/test_runner.dart

 // Copyright (c) 2012, 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.
 
 /**
  * Classes and methods for executing tests.
  *
  * This module includes:
  * - Managing parallel execution of tests, including timeout checks.
  * - Evaluating the output of each test as pass/fail/crash/timeout.
@@ skipping 434 matching lines @@
   JSCommandlineCommand._(
       String displayName, String executable, List<String> arguments,
       [Map<String, String> environmentOverrides = null])
       : super._(displayName, executable, arguments, environmentOverrides);
 }
 
 class PubCommand extends ProcessCommand {
   final String command;
 
   PubCommand._(String pubCommand, String pubExecutable,
-      String pubspecYamlDirectory, String pubCacheDirectory)
+      String pubspecYamlDirectory, String pubCacheDirectory, List<String> args)
       : super._(
             'pub_$pubCommand',
             new io.File(pubExecutable).absolute.path,
-            [pubCommand],
+            [pubCommand]..addAll(args),
             {'PUB_CACHE': pubCacheDirectory},
             pubspecYamlDirectory),
         command = pubCommand;
 
   void _buildHashCode(HashCodeBuilder builder) {
     super._buildHashCode(builder);
     builder.addJson(command);
   }
 
   bool _equal(PubCommand other) =>
@@ skipping 218 matching lines @@
     return _getUniqueCommand(command);
   }
 
   Command getCopyCommand(String sourceDirectory, String destinationDirectory) {
     var command =
         new CleanDirectoryCopyCommand._(sourceDirectory, destinationDirectory);
     return _getUniqueCommand(command);
   }
 
   Command getPubCommand(String pubCommand, String pubExecutable,
-      String pubspecYamlDirectory, String pubCacheDirectory) {
+      String pubspecYamlDirectory, String pubCacheDirectory,
+      {List<String> arguments: const <String>[]}) {
     var command = new PubCommand._(
-        pubCommand, pubExecutable, pubspecYamlDirectory, pubCacheDirectory);
+        pubCommand, pubExecutable, pubspecYamlDirectory, pubCacheDirectory,
+        arguments);
     return _getUniqueCommand(command);
   }
 
   Command getMakeSymlinkCommand(String link, String target) {
     return _getUniqueCommand(new MakeSymlinkCommand._(link, target));
   }
 
   Command _getUniqueCommand(Command command) {
     // All Command classes implement hashCode and operator==.
     // We check if this command has already been built.
@@ skipping 2596 matching lines @@
     }
   }
 
   void eventAllTestsDone() {
     for (var listener in _eventListener) {
       listener.allDone();
     }
     _allDone();
   }
 }