Support --special-command test option. As a special case support --valgrind option.

tests/standalone/src/TestRunnerTest.dart

 // Copyright (c) 2011, 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("TestRunnerTest");
 
 #import("../../../tools/testing/dart/test_runner.dart");
 #import("../../../tools/testing/dart/status_file_parser.dart");
 #source("ProcessTestUtil.dart");
 
@@ skipping 25 matching lines @@
 }
 
 
 TestCase MakeTestCase(String testName, List<String> expectations) {
   String test_path = "tests/standalone/src/${testName}.dart";
   // Working directory may be dart/runtime rather than dart.
   if (!new File(test_path).existsSync()) {
     test_path = "../tests/standalone/src/${testName}.dart";
   }
 
-  var timeout = 2;
+  var configuration = { 'timeout': 2,
+                        'special-command': '' };
   return new TestCase(testName,
                       getDartFileName(),
                       <String>["--ignore-unrecognized-flags",
                                "--enable_type_checks",
                                test_path],
-                      timeout,
+                      configuration,
                       TestController.processCompletedTest,
                       new Set<String>.from(expectations));
 }
 
 
 void main() {
-  int timeout = 2;
+  var configuration = { 'timeout': 2,
+                        'special-command': '' };
   new RunningProcess(MakeTestCase("PassTest", [PASS])).start();
   new RunningProcess(MakeTestCase("FailTest", [FAIL])).start();
   new RunningProcess(MakeTestCase("TimeoutTest", [TIMEOUT])).start();
 
   new RunningProcess(new TestCase("CrashTest",
                                   getProcessTestFileName(),
                                   const ["0", "0", "1", "1"],
-                                  timeout,
+                                  configuration,
                                   TestController.processCompletedTest,
                                   new Set<String>.from([CRASH]))).start();
   Expect.equals(4, TestController.numTests);
   // Throw must be from body of start() function for this test to work.
   Expect.throws(new RunningProcess(MakeTestCase("PassTest", [SKIP])).start);
 }