Add --time option to dart test scripts.

tools/testing/dart/test_runner.dart

Index: tools/testing/dart/test_runner.dart
diff --git a/tools/testing/dart/test_runner.dart b/tools/testing/dart/test_runner.dart
index 29692b0cc3066495c774b1a11d76f61908fcfdd4..23fefe49b3e514b9392416ae74d342672ce6e581 100644
--- a/tools/testing/dart/test_runner.dart
+++ b/tools/testing/dart/test_runner.dart
@@ -331,10 +331,13 @@ class ProcessQueue {
   ProcessQueue(int this._maxProcesses,
                String progress,
                bool this._verbose,
-               Date start_time,
+               Date startTime,
+               bool printTiming,
                Function this._enqueueMoreWork)
       : _tests = new Queue<TestCase>(),
-        _progress = new ProgressIndicator.fromName(progress, start_time),
+        _progress = new ProgressIndicator.fromName(progress,
+                                                   startTime,
+                                                   printTiming),
         _batchProcesses = new List<DartcBatchRunnerProcess>() {
     if (!_enqueueMoreWork(this)) _progress.allDone();
   }