Make DeferredNotLoadedError be a NuSuchMethodError

sdk/lib/_internal/lib/js_helper.dart

 // Copyright (c) 2013, 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 _js_helper;
 
 import 'dart:collection';
 import 'dart:_isolate_helper' show
     IsolateNatives,
     leaveJsAsync,
@@ skipping 2771 matching lines @@
 
 /**
  * Error thrown when a runtime error occurs.
  */
 class RuntimeError extends Error {
   final message;
   RuntimeError(this.message);
   String toString() => "RuntimeError: $message";
 }
 
-class DeferredNotLoadedError extends Error {
+class DeferredNotLoadedError extends Error implements NoSuchMethodError {
   String libraryName;
 
   DeferredNotLoadedError(this.libraryName);
 
   String toString() {
     return "Deferred library $libraryName was not loaded.";
   }
 }
 
 abstract class RuntimeType {
@@ skipping 509 matching lines @@
     JS('', '#.addEventListener("error", #, false)',
        script, convertDartClosureToJS((event) {
       completer.completeError(
           new DeferredLoadException("Loading $uri failed."));
     }, 1));
     JS('', 'document.body.appendChild(#)', script);
 
     return completer.future;
   });
 }