Fix for incremental resolution in case of inserting a new token into elegant comments.

pkg/analyzer/test/generated/incremental_resolver_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 engine.incremental_resolver_test;
 
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/error.dart';
@@ skipping 2761 matching lines @@
 }
 ''');
     _updateAndValidate(r'''
 /// aaa bbb
 main() {
   return 2;
 }
 ''');
   }
 
+  void test_dartDoc_elegant_updateText_insertToken() {
+    _resolveUnit(r'''
+/// A
+/// [int]
+class Test {
+}
+''');
+    _updateAndValidate(r'''
+/// A
+///
+/// [int]
+class Test {
+}
+''');
+  }
+
+  void test_dartDoc_elegant_updateText_removeToken() {
+    _resolveUnit(r'''
+/// A
+///
+/// [int]
+class Test {
+}
+''');
+    _updateAndValidate(r'''
+/// A
+/// [int]
+class Test {
+}
+''');
+  }
+
   void test_endOfLineComment_add_beforeKeywordToken() {
     _resolveUnit(r'''
 main() {
   var v = 42;
 }
 ''');
     _updateAndValidate(r'''
 main() {
   // some comment
   var v = 42;
@@ skipping 984 matching lines @@
   }
 }
 
 
 class _Edit {
   final int offset;
   final int length;
   final String replacement;
   _Edit(this.offset, this.length, this.replacement);
 }