Change output of test.dart --list option, so it can be parsed automatically.

tools/testing/dart/test_progress.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.
 
 #library("test_progress");
 
 #import("dart:io");
 #import("test_runner.dart");
 #import("test_suite.dart");
 
 class ProgressIndicator {
   ProgressIndicator(this._startTime, this._printTiming)
       : _tests = [], _failureSummary = [];
 
   factory ProgressIndicator.fromName(String name,
                                      Date startTime,
                                      bool printTiming) {
     switch (name) {
       case 'compact':
         return new CompactProgressIndicator(startTime, printTiming);
       case 'color':
         return new ColorProgressIndicator(startTime, printTiming);
       case 'line':
         return new LineProgressIndicator(startTime, printTiming);
       case 'verbose':
         return new VerboseProgressIndicator(startTime, printTiming);
+      case 'silent':
+        return new SilentProgressIndicator(startTime, printTiming);
       case 'status':
         return new StatusProgressIndicator(startTime, printTiming);
       case 'buildbot':
         return new BuildbotProgressIndicator(startTime, printTiming);
       default:
         assert(false);
         break;
     }
   }
 
@@ skipping 139 matching lines @@
   int _passedTests = 0;
   int _failedTests = 0;
   bool _allTestsKnown = false;
   Date _startTime;
   bool _printTiming;
   List<TestCase> _tests;
   List<String> _failureSummary;
 }
 
 
+class SilentProgressIndicator extends ProgressIndicator {
+  SilentProgressIndicator(Date startTime, bool printTiming)
+      : super(startTime, printTiming);
+  void testAdded() { }
+  void start(TestCase test) { }
+  void done(TestCase test) { }
+  void allTestsKnown() { }
+  void allDone() {
+    exit(0);
+  }
+}
+
 class CompactIndicator extends ProgressIndicator {
   CompactIndicator(Date startTime, bool printTiming)
       : super(startTime, printTiming);
 
   void allDone() {
     stdout.write('\n'.charCodes());
     _printFailureSummary();
     _printTimingInformation();
     if (_failedTests > 0) {
       // We may have printed many failure logs, so reprint the summary data.
@@ skipping 131 matching lines @@
     var status = 'pass';
     if (test.output.unexpectedOutput) {
       status = 'fail';
     }
     var percent = ((_completedTests() / _foundTests) * 100).toInt().toString();
     print('Done ${test.configurationString} ${test.displayName}: $status');
     print('@@@STEP_CLEAR@@@');
     print('@@@STEP_TEXT@ $percent% +$_passedTests -$_failedTests @@@');
   }
 }