More fixing tests to make bots happy.

test/utils.dart

 // 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 dart_style.test.utils;
 
 import 'dart:io';
 
 import 'package:path/path.dart' as p;
 import 'package:scheduled_test/descriptor.dart' as d;
 import 'package:scheduled_test/scheduled_process.dart';
 import 'package:scheduled_test/scheduled_test.dart';
 import 'package:unittest/compact_vm_config.dart';
 
 const unformattedSource = 'void  main()  =>  print("hello") ;';
 const formattedSource = 'void main() => print("hello");\n';
 
 /// Runs the command line formatter, passing it [args].
 ScheduledProcess runFormatter([List<String> args]) {
   if (args == null) args = [];
 
   var formatterPath = p.join(
       p.dirname(p.fromUri(Platform.script)), "..", "bin", "format.dart");
 
-  args.insertAll(0, ["--package-root=${Platform.packageRoot}", formatterPath]);
+  args.insert(0, formatterPath);
+
+  // Use the same package root, if there is one.
+  if (Platform.packageRoot.isNotEmpty) {
+    args.insert(0, "--package-root=${Platform.packageRoot}");
+  }
+
   return new ScheduledProcess.start(Platform.executable, args);
 }
 
 /// Runs the command line formatter, passing it the test directory followed by
 /// [args].
 ScheduledProcess runFormatterOnDir([List<String> args]) {
   if (args == null) args = [];
   return runFormatter([d.defaultRoot]..addAll(args));
 }
 
@@ skipping 11 matching lines @@
   setUp(() {
     var tempDir = Directory.systemTemp.createTempSync('dart_style.test.');
     d.defaultRoot = tempDir.path;
 
     currentSchedule.onComplete.schedule(() {
       d.defaultRoot = null;
       return tempDir.delete(recursive: true);
     });
   });
 }