Replace assert_promise_rejects with upstream promise_rejects.

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

 if (self.importScripts) {
     importScripts('/resources/testharness.js');
-    importScripts('/resources/testharness-helpers.js');
     importScripts('../resources/test-helpers.js');
 }
 
 promise_test(function(t) {
     var cache_name = 'cache-storage/foo';
     return self.caches.delete(cache_name)
       .then(function() {
           return self.caches.open(cache_name);
         })
       .then(function(cache) {
@@ skipping 10 matching lines @@
       .then(function() {
           return self.caches.open(cache_name);
         })
       .then(function(cache) {
           assert_true(cache instanceof Cache,
                       'CacheStorage.open should accept an empty name.');
         });
   }, 'CacheStorage.open with an empty name');
 
 promise_test(function(t) {
-    return assert_promise_rejects(
+    return promise_rejects(
+      t,
+      new TypeError(),
       self.caches.open(),
-      new TypeError(),
       'CacheStorage.open should throw TypeError if called with no arguments.');
   }, 'CacheStorage.open with no arguments');
 
 promise_test(function(t) {
     var test_cases = [
       {
         name: 'cache-storage/lowercase',
         should_not_match:
           [
             'cache-storage/Lowercase',
@@ skipping 141 matching lines @@
                       'CacheStorage names should be not be converted.');
         })
       .then(function() { return self.caches.has(converted_name); })
       .then(function(cache_exists) {
           assert_false(cache_exists,
                        'CacheStorage names should be not be converted.');
         });
   }, 'CacheStorage names are DOMStrings not USVStrings');
 
 done();