Implement chromium component.

tools/testing/dart/test_options.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_options_parser");
 
 List<String> defaultTestSelectors =
     const ['dartc', 'samples', 'standalone', 'corelib', 'co19', 'language',
            'isolate', 'stub-generator', 'vm'];
 
@@ skipping 43 matching lines @@
         [ new _TestOptionSpecification(
               'mode',
               'Mode in which to run the tests',
               ['-m', '--mode'],
               ['all', 'debug', 'release'],
               'debug'),
           new _TestOptionSpecification(
               'component',
               'The component to test against',
               ['-c', '--component'],
-              ['most', 'vm', 'dartc', 'frog', 'frogsh', 'leg', 'dartium'],
+              ['most', 'vm', 'dartc', 'frog', 'frogsh', 'leg',
+               'dartium', 'chromium'],
               'vm'),
           new _TestOptionSpecification(
               'arch',
               'The architecture to run tests for',
               ['-a', '--arch'],
               ['all', 'ia32', 'x64', 'simarm'],
               'ia32'),
           new _TestOptionSpecification(
               'system',
               'The operating system to run tests on',
@@ skipping 349 matching lines @@
       if (option.keys.some((key) => key == name)) {
         return option;
       }
     }
     return null;
   }
 
 
   List<_TestOptionSpecification> _options;
 }