fix #30094, assert should work with a function

pkg/dev_compiler/test/browser/language_tests.js

 // Copyright (c) 2015, 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.
 
 define(['dart_sdk', 'async_helper', 'expect', 'unittest', 'is', 'require'],
       function(dart_sdk, async_helper, expect, unittest, is, require) {
   'use strict';
 
   async_helper = async_helper.async_helper;
   let minitest = expect.minitest;
@@ skipping 41 matching lines @@
   const async_unittest = ['unittest', 'skip', 'fail'];
 
   // The number of expected unittest errors should be zero but unfortunately
   // there are a lot of broken html unittests.
   let num_expected_unittest_fails = 4;
   let num_expected_unittest_errors = 0;
 
   // TODO(jmesserly): separate StrongModeError from other errors.
   let all_status = {
     'language': {
-      'assertion_test': fail,
       'async_await_test_none_multi': 'unittest',
       'async_await_test_02_multi': 'unittest',
 
       // Flaky on travis (https://github.com/dart-lang/sdk/issues/27224)
       'async_await_test_03_multi': async_unittest,
 
       'async_star_await_pauses_test': skip_timeout,
 
       // TODO(jmesserly): figure out why this test is hanging.
       'async_star_cancel_and_throw_in_finally_test': skip_timeout,
@@ skipping 831 matching lines @@
 
     for (let action of unittest_tests) {
       try {
         action();
       } catch (e) {
         console.error("Caught error tying to setup test:", e);
       }
     }
   });
 });