Fix for webdriver_test_setup in Windows, and don't force close of the browsers if we're not running…

tools/testing/dart/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.
 
 /**
  * Classes and methods for executing tests.
  *
  * This module includes:
  * - Managing parallel execution of tests, including timeout checks.
  * - Evaluating the output of each test as pass/fail/crash/timeout.
@@ skipping 887 matching lines @@
         };
       }
     }
   }
 
   /**
    * Perform any cleanup needed once all tests in a TestSuite have completed
    * and notify our progress indicator that we are done.
    */
   void _cleanupAndMarkDone() {
-    if (browserUsed != '') {
+    if (browserUsed != '' && _progress is BuildbotProgressIndicator) {
       killZombieBrowsers();
       if (_seleniumServer != null) {
         _seleniumServer.kill();
       }
     } else {
       _progress.allDone();
     }
   }
 
   void _checkDone() {
@@ skipping 207 matching lines @@
         // the developer doesn't waste his or her time trying to fix a bunch of
         // tests that appear to be broken but were actually just flakes that
         // didn't get retried because there had already been one failure.
         bool allowRetry = _MAX_FAILED_NO_RETRY > _progress.numFailedTests;
         new RunningProcess(test, allowRetry, this).start();
       }
       _numProcesses++;
     }
   }
 }