Remove spaces from group names in node_validator_test

tests/html/node_validator_test.dart

 // Copyright (c) 2013, 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 validator_test;
 
 import 'dart:html';
 import 'dart:svg' as svg;
 import 'package:unittest/unittest.dart';
 import 'package:unittest/html_individual_config.dart';
@@ skipping 35 matching lines @@
       reference = html;
     }
 
     validateHtml(html, reference, validator);
   });
 }
 
 main() {
   useHtmlIndividualConfiguration();
 
-  group('DOM sanitization', () {
+  group('DOM_sanitization', () {
     var validator = new NodeValidatorBuilder.common();
 
     testHtml('allows simple constructs',
         validator,
         '<div class="baz">something</div>');
 
     testHtml('blocks unknown attributes',
         validator,
         '<div foo="baz">something</div>',
         '<div>something</div>');
@@ skipping 439 matching lines @@
     validator,
     "<form onmouseover='alert(2)'><input name='tagName'>",
     "");
 
     testHtml('tagName without mouseover',
     validator,
     "<form><input name='tagName'>",
     "");
   });
 }