Remove ProcessOptions and make the options named arguments.

tests/standalone/io/process_environment_test.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.
 
 import "package:expect/expect.dart";
 import "dart:io";
 import "dart:isolate";
 import "process_test_util.dart";
 
 runEnvironmentProcess(Map environment, name, callback) {
   var dartExecutable = new Options().executable;
-  var options = new ProcessOptions();
-  options.environment = environment;
   var printEnv = 'tests/standalone/io/print_env.dart';
   if (!new File(printEnv).existsSync()) {
     printEnv = '../$printEnv';
   }
-  Process.run(dartExecutable, [printEnv, name], options).then((result) {
-    Expect.equals(0, result.exitCode);
-    callback(result.stdout);
-  });
+  Process.run(dartExecutable,
+              [printEnv, name],
+              environment: environment)
+      .then((result) {
+        Expect.equals(0, result.exitCode);
+        callback(result.stdout);
+      });
 }
 
 testEnvironment() {
   var donePort = new ReceivePort();
   Map env = Platform.environment;
   Expect.isFalse(env.isEmpty);
   // Check that some value in the environment stays the same when passed
   // to another process.
   for (var k in env.keys) {
     runEnvironmentProcess(env, k, (output) {
@@ skipping 13 matching lines @@
     });
     // Only check one value to not spin up too many processes testing the
     // same things.
     break;
   }
 }
 
 main() {
   testEnvironment();
 }