Replace assert_promise_rejects with upstream promise_rejects.

third_party/WebKit/LayoutTests/http/tests/cachestorage/script-tests/cache-match.js

 if (self.importScripts) {
     importScripts('/resources/testharness.js');
-    importScripts('/resources/testharness-helpers.js');
     importScripts('../resources/test-helpers.js');
 }
 
 prepopulated_cache_test(simple_entries, function(cache, entries) {
     return cache.match('not-present-in-the-cache')
       .then(function(result) {
           assert_equals(result, undefined,
                         'Cache.match failures should resolve with undefined.');
         });
   }, 'Cache.match with no matching entries');
@@ skipping 217 matching lines @@
     return cache.match(entries.error_response.request.url)
       .then(function(result) {
           assert_response_equals(
               result, entries.error_response.response,
               'Cache.match should return a Response object that has the ' +
                   'same properties as a stored network error response.');
         });
   }, 'Cache.match with a network error Response');
 
 done();