anchor.diff:        try {
           request.response.statusCode = HttpStatus.INTERNAL_SERVER_ERROR;
         } on StateError catch (_) {}
  -      request.response.close().catchError((_) {
  +      request.response.close().catchError((closeError, closeErrorStack) {
           errorHandler('Forcefully closing response, due to error in request '
  -                     'handler zone, resulted in an error: $error', stack);
  +                     'handler zone, resulted in an error: $closeError',
  +                     closeErrorStack);
         });
       });
     });
  
positive.code: 
  const Symbol _APPENGINE_CONTEXT = #appengine_context;
  
  ClientContext contextFromRequest(HttpRequest request) {
    return appengine_internal.contextFromRequest(request);
  }
  
  Future runAppEngineRaw(AppEngineRequestHandler handler) {
    return appengine_internal.runAppEngine(handler);
  }
  
  Future runAppEngine(AppEngineRequestHandler handler, {Function onError}) {
    var errorHandler;
    if (onError != null) {
  
negative.code: /**
   * Returns the [ClientContext] of the current request.
   *
   * This getter can only be called inside a request handler which was passed to
   * [runAppEngine].
   */
  ClientContext get context {
    var context = Zone.current[_APPENGINE_CONTEXT];
  