Invalidate defaultObjects if timezone changes

src/js/i18n.js

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // ECMAScript 402 API implementation.
 
 /**
  * Intl object is a single object that has some named properties,
  * all of which are constructors.
  */
@@ skipping 1971 matching lines @@
 // Default (created with undefined locales and options parameters) collator,
 // number and date format instances. They'll be created as needed.
 var defaultObjects = {
   'collator': UNDEFINED,
   'numberformat': UNDEFINED,
   'dateformatall': UNDEFINED,
   'dateformatdate': UNDEFINED,
   'dateformattime': UNDEFINED,
 };
 
+function clearDefaultObjects() {
+  defaultObjects['dateformatall'] = UNDEFINED;
+  defaultObjects['dateformatdate'] = UNDEFINED;
+  defaultObjects['dateformattime'] = UNDEFINED;
+}
+
+var date_cache_version = 0;
+
+function checkDateCacheCurrent() {
+  var new_date_cache_version = %DateCacheVersion();
+  if (new_date_cache_version == date_cache_version) {
+    return;
+  }
+  date_cache_version = new_date_cache_version;
+
+  clearDefaultObjects();
+}
 
 /**
  * Returns cached or newly created instance of a given service.
  * We cache only default instances (where no locales or options are provided).
  */
 function cachedOrNewService(service, locales, options, defaults) {
   var useOptions = (IS_UNDEFINED(defaults)) ? options : defaults;
   if (IS_UNDEFINED(locales) && IS_UNDEFINED(options)) {
+    checkDateCacheCurrent();
     if (IS_UNDEFINED(defaultObjects[service])) {
       defaultObjects[service] = new savedObjects[service](locales, useOptions);
     }
     return defaultObjects[service];
   }
   return new savedObjects[service](locales, useOptions);
 }
 
 function LocaleConvertCase(s, locales, isToUpper) {
   // ECMA 402 section 13.1.2 steps 1 through 12.
@@ skipping 222 matching lines @@
   }
 );
 
 utils.Export(function(to) {
   to.AddBoundMethod = AddBoundMethod;
   to.IntlParseDate = IntlParseDate;
   to.IntlParseNumber = IntlParseNumber;
 });
 
 })