Add a failing integration test

pkg/analysis_server/test/integration/analysis/update_content_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.
 
 import 'package:analysis_server/plugin/protocol/protocol.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 import '../integration_tests.dart';
 
@@ skipping 41 matching lines @@
     });
     await analysisFinished;
     expect(currentAnalysisErrors[path], isEmpty);
 
     // Now there should be errors again, because the contents on disk are no
     // longer overridden.
     sendAnalysisUpdateContent({path: new RemoveContentOverlay()});
     await analysisFinished;
     expect(currentAnalysisErrors[path], isNotEmpty);
   }
+
+  @failingTest
+  test_updateContent_multipleAdds() async {
+    String pathname = sourcePath('test.dart');
+    writeFile(
+        pathname,
+        r'''
+class Person {
+  String _name;
+  Person(this._name);
+  String get name => this._name;
+  String toString() => "Name: ${name}";
+}
+void main() {
+  var p = new Person("Skeletor");
+  p.xname = "Faker";
+  print(p);
+}
+''');
+    standardAnalysisSetup();
+    await analysisFinished;
+    expect(currentAnalysisErrors[pathname], isList);
+    List<AnalysisError> errors1 = currentAnalysisErrors[pathname];
+    expect(errors1, hasLength(1));
+    expect(errors1[0].location.file, equals(pathname));
+
+    await sendAnalysisUpdateContent({
+      pathname: new AddContentOverlay(r'''
+class Person {
+  String _name;
+  Person(this._name);
+  String get name => this._name;
+  String toString() => "Name: ${name}";
+}
+void main() {
+  var p = new Person("Skeletor");
+  p.name = "Faker";
+  print(p);
+}
+''')
+    });
+    await analysisFinished;
+    expect(currentAnalysisErrors[pathname], isList);
+    List<AnalysisError> errors2 = currentAnalysisErrors[pathname];
+    expect(errors2, hasLength(1));
+    expect(errors2[0].location.file, equals(pathname));
+  }
 }
 
 @reflectiveTest
 class UpdateContentTest extends AbstractUpdateContentTest {}
 
 @reflectiveTest
 class UpdateContentTest_Driver extends AbstractUpdateContentTest {
   @override
   bool get enableNewAnalysisDriver => true;
 }