Roll back "Use package:stack_trace in unittest."

utils/testrunner/standard_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.
 
 part of test_controller;
 
 /** Path to DRT executable. */
 String drt;
 
 /** Whether to include elapsed time. */
@@ skipping 181 matching lines @@
 // Support for running in isolates.
 
 class TestRunnerChildConfiguration extends Configuration {
   get name => 'Test runner child configuration';
   get autoStart => false;
 
   void onSummary(int passed, int failed, int errors,
       List<TestCase> results, String uncaughtError) {
     TestCase test = results[0];
     parentPort.send([test.result, test.runningTime.inMilliseconds,
-                     test.message, test.stackTrace.toString()]);
+                     test.message, test.stackTrace]);
   }
 }
 
 var parentPort;
 runChildTest() {
   port.receive((testName, sendport) {
     parentPort = sendport;
     unittestConfiguration = new TestRunnerChildConfiguration();
     groupSep = marker;
     group('', test.main);
@@ skipping 47 matching lines @@
 }
 
 process(testMain, action) {
   groupSep = marker;
   unittestConfiguration = new TestRunnerConfiguration();
   group('', testMain);
   // Do any user-specified test filtering.
   filterTests(filterTest);
   action();
 }