Implement removal of top-level methods.

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 275 matching lines @@
 main() {
   if (instance == null) {
     instance = new C();
   }
   instance.m();
 }
 """,
             const <String> ['v2']),
     ],
 
+    // Test that deleting a top-level method works.
+    const <ProgramResult>[
+        const ProgramResult(
+            """
+toplevel() {
+  print('v1');
+}
+class C {
+  m() {
+    try {
+      toplevel();
+    } catch (e) {
+      print('v2');
+    }
+  }
+}
+var instance;
+main() {
+  if (instance == null) {
+    instance = new C();
+  }
+  instance.m();
+}
+""",
+            const <String> ['v1']),
+        const ProgramResult(
+            """
+class C {
+  m() {
+    try {
+      toplevel();
+    } catch (e) {
+      print('v2');
+    }
+  }
+}
+var instance;
+main() {
+  if (instance == null) {
+    instance = new C();
+  }
+  instance.m();
+}
+""",
+            const <String> ['v2']),
+    ],
+
+
+
 ];
 
 void main() {
   listener.start();
 
   return asyncTest(() => Future.forEach(tests, compileAndRun));
 }
 
 Future compileAndRun(List<ProgramResult> programs) {
   var status = new DivElement();
@@ skipping 51 matching lines @@
 
 void logger(x) {
   print(x);
   bool isCheckedMode = false;
   assert(isCheckedMode = true);
   int timeout = isCheckedMode ? TIMEOUT * 2 : TIMEOUT;
   if (listener.elapsed > timeout) {
     throw 'Test timed out.';
   }
 }