Update name of content-shell flag --run-layout-test in test scripts

tools/testing/dart/test_suite.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 enumerating and preparing tests.
  *
  * This library includes:
  *
  * - Creating tests by listing all the Dart files in certain directories,
@@ skipping 1264 matching lines @@
 
       var htmlPath_subtest = _createUrlPathFromFile(new Path(htmlPath));
       var fullHtmlPath =
           _getUriForBrowserTest(htmlPath_subtest, subtestName).toString();
 
       if (runtime == "drt") {
         var dartFlags = [];
         var contentShellOptions = [];
 
         contentShellOptions.add('--no-timeout');
-        contentShellOptions.add('--dump-render-tree');
+        contentShellOptions.add('--run-layout-test');
 
         // Disable the GPU under Linux and Dartium. If the GPU is enabled,
         // Chrome may send a termination signal to a test.  The test will be
         // terminated if a machine (bot) doesn't have a GPU or if a test is
         // still running after a certain period of time.
         if (configuration['system'] == 'linux' &&
             configuration['runtime'] == 'drt') {
           contentShellOptions.add('--disable-gpu');
         }
         if (compiler == 'none') {
@@ skipping 1124 matching lines @@
       }
       if (path.length > WINDOWS_SHORTEN_PATH_LIMIT) {
         ++shortNameCounter;
         var pathEnd = path.substring(path.length - WINDOWS_PATH_END_LENGTH);
         path = "short${shortNameCounter}_$pathEnd";
       }
     }
     return path;
   }
 }