Revert "Clean up process spawning."

tests/standalone/io/platform_resolved_executable_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.
 //
 // Process test program to test process communication.
 
 library PlatformExecutableTest;
 
 import "dart:io";
 
@@ skipping 25 matching lines @@
 
   var result = processResult.stdout.trim();
   expectEquals(Platform.resolvedExecutable, result);
 }
 
 void testDartExecShouldNotBeInCurrentDir() {
   var type = FileSystemEntity.typeSync(platformExeName);
   expectEquals(FileSystemEntityType.NOT_FOUND, type);
 }
 
-void testShouldSucceedWithEmptyPathEnvironment() {
-  var command = Platform.isWindows ? 'cmd' : 'ls';
-  Process.runSync(command, [],
-                  includeParentEnvironment: false,
-                  environment: {_SCRIPT_KEY: 'yes', 'PATH': ''});
+void testShouldFailOutsidePath() {
+  var threw = false;
+  try {
+    Process.runSync(platformExeName, ['--version'],
+                    includeParentEnvironment: false,
+                    environment: {_SCRIPT_KEY: 'yes', 'PATH': ''});
+  } catch (_) {
+    threw = true;
+  }
+
+  if (!threw) {
+    throw 'Expected running the dart executable – "$platformExeName" without'
+          ' the parent environment or path to fail.';
+  }
 }
 
 void testShouldSucceedWithSourcePlatformExecutable() {
   verify(Platform.resolvedExecutable);
 }
 
 void testExeSymLinked(Directory dir) {
   var dirUri = new Uri.directory(dir.path);
   var link = new Link.fromUri(dirUri.resolve('dart_exe_link'));
   link.createSync(Platform.resolvedExecutable);
@@ skipping 76 matching lines @@
   if (!Platform.isWindows) {
     withTempDir(testExeSymLinked); /// 01: ok
   }
   withTempDir(testExeDirSymLinked); /// 02: ok
   testPathToSDKDir(); /// 03: ok
   withTempDir(testPathPointsToSymLinkedSDKPath); /// 04: ok
   // dart:io does not support linking to files in Windows.
   if (!Platform.isWindows) {
     withTempDir(testPathToDirWithExeSymLinked); /// 05: ok
   }
-  testShouldSucceedWithEmptyPathEnvironment(); /// 06: ok
+  testShouldFailOutsidePath(); /// 06: ok
 }