Incremental compilation of added instance fields.

dart/tests/try/web/incremental_compilation_update_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 trydart.incremental_compilation_update_test;
 
 import 'dart:html';
 
 import 'dart:async' show
     Future;
@@ skipping 888 matching lines @@
 
 main() {
   if (instance == null) {
     instance = new C();
   }
   instance.m();
 }
 """,
             const <String>['v2']),
     ],
+
+    // Test adding a field to a class works.
+    const <ProgramResult>[
+        const ProgramResult(
+            r"""
+class A {
+}
+
+var instance;
+
+main() {
+  if (instance == null) {
+    instance = new A();
+  }
+  try {
+    instance.x = 'v2';
+  } catch(e) {
+    print('setter threw');
+  }
+  try {
+    print(instance.x);
+  } catch (e) {
+    print('getter threw');
+  }
+}
+""",
+            const <String>['setter threw', 'getter threw']),
+        const ProgramResult(
+            r"""
+class A {
+  var x;
+}
+
+var instance;
+
+main() {
+  if (instance == null) {
+    instance = new A();
+  }
+  try {
+    instance.x = 'v2';
+  } catch(e) {
+    print('setter threw');
+  }
+  try {
+    print(instance.x);
+  } catch (e) {
+    print('getter threw');
+  }
+}
+""",
+            const <String>['v2']),
+    ],
 ];
 
 void main() {
   listener.start();
 
   document.head.append(lineNumberStyle());
 
   return asyncTest(() => Future.forEach(tests, compileAndRun));
 }
 
@@ skipping 106 matching lines @@
   position: absolute;
   left: 0px;
   width: 3em;
   text-align: right;
   background-color: lightgoldenrodyellow;
 }
 ''');
   style.type = 'text/css';
   return style;
 }