Fix for highlighting 'abstract' in ClassTypeAlias.

pkg/analysis_server/test/analysis/notification_highlights_test.dart

 // Copyright (c) 2014, 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.analysis.notification.highlights;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/protocol.dart';
@@ skipping 118 matching lines @@
 @AAA main() {}
 ''');
     return prepareHighlights().then((_) {
       assertHasRegion(HighlightRegionType.ANNOTATION, '@AAA');
     });
   }
 
   test_BUILT_IN_abstract() {
     addTestFile('''
 abstract class A {};
+abstract class B = Object with A;
 main() {
   var abstract = 42;
 }''');
     return prepareHighlights().then((_) {
-      assertHasRegion(HighlightRegionType.BUILT_IN, 'abstract class');
+      assertHasRegion(HighlightRegionType.BUILT_IN, 'abstract class A');
+      assertHasRegion(HighlightRegionType.BUILT_IN, 'abstract class B');
       assertNoRegion(HighlightRegionType.BUILT_IN, 'abstract = 42');
     });
   }
 
   test_BUILT_IN_as() {
     addTestFile('''
 import 'dart:math' as math;
 main() {
   p as int;
   var as = 42;
@@ skipping 778 matching lines @@
   void test_toString() {
     expect(HighlightRegionType.CLASS.toString(), 'HighlightRegionType.CLASS');
   }
 
   void test_valueOf_unknown() {
     expect(() {
       new HighlightRegionType('no-such-type');
     }, throws);
   }
 }