Make the repeating argument to timers optional.

tools/testing/dart/test_suite.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("test_suite");
 
 #import("status_file_parser.dart");
 #import("test_runner.dart");
 #import("multitest.dart");
 
@@ skipping 176 matching lines @@
           processDirectory();
         } else {
           // We rely on enqueueing completing asynchronously so use a
           // timer to make it so.
           void enqueueCachedTests(Timer ignore) {
             for (var info in testCache[suiteName]) {
               enqueueTestCaseFromTestInformation(info);
             }
             doDone();
           }
-          new Timer(enqueueCachedTests, 0, false);
+          new Timer(enqueueCachedTests, 0);
         }
       }
     }
 
     // Read test expectations from status files.
     testExpectations =
         new TestExpectations(complexMatching: complexStatusMatching());
     for (var statusFilePath in statusFilePaths) {
       ReadTestExpectationsInto(testExpectations,
                                statusFilePath,
@@ skipping 514 matching lines @@
  * $noCrash tests are expected to be flaky but not crash
  * $pass tests are expected to pass
  * $failOk tests are expected to fail that we won't fix
  * $fail tests are expected to fail that we should fix
  * $crash tests are expected to crash that we should fix
  * $timeout tests are allowed to timeout\
 """;
     print(report);
   }
 }