Improved HTML parsing

editor/tools/plugins/com.google.dart.engine_test/src/com/google/dart/engine/internal/html/HtmlTagInfoBuilderTest.java

 /*
  * Copyright (c) 2013, the Dart project authors.
  * 
  * Licensed under the Eclipse Public License v1.0 (the "License"); you may not use this file except
  * in compliance with the License. You may obtain a copy of the License at
  * 
  * http://www.eclipse.org/legal/epl-v10.html
  * 
  * Unless required by applicable law or agreed to in writing, software distributed under the License
  * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
  * or implied. See the License for the specific language governing permissions and limitations under
  * the License.
  */
 package com.google.dart.engine.internal.html;
 
 import com.google.dart.engine.EngineTestCase;
+import com.google.dart.engine.error.GatheringErrorListener;
 import com.google.dart.engine.html.parser.HtmlParseResult;
 import com.google.dart.engine.html.parser.HtmlParser;
 import com.google.dart.engine.html.scanner.HtmlScanResult;
 import com.google.dart.engine.html.scanner.HtmlScanner;
 import com.google.dart.engine.source.SourceFactory;
 import com.google.dart.engine.source.TestSource;
 
 import static com.google.dart.engine.utilities.io.FileUtilities2.createFile;
 
 public class HtmlTagInfoBuilderTest extends EngineTestCase {
@@ skipping 19 matching lines @@
 
   private HtmlParseResult parse(String contents) throws Exception {
     SourceFactory factory = new SourceFactory();
     TestSource source = new TestSource(
         factory.getContentCache(),
         createFile("/test.dart"),
         contents);
     HtmlScanner scanner = new HtmlScanner(source);
     source.getContents(scanner);
     HtmlScanResult scanResult = scanner.getResult();
-    HtmlParseResult result = new HtmlParser(source).parse(scanResult);
+    GatheringErrorListener errorListener = new GatheringErrorListener();
+    HtmlParseResult result = new HtmlParser(source, errorListener).parse(scanResult);
+    errorListener.assertNoErrors();
     return result;
   }
 }