Invalidate defaultObjects if timezone changes

In case of calling 'toLocaleString', 'toLocaleTimeString' and
'toLocaleDateString' functions of 'Date' with empty 'locales' and
'options', DateTimeFormat is cached inside 'defaultObjects'.
If we change the timezone the cache is not invalidated.

BUG=v8:5022
TEST=cctest:DateCacheVersion. See the bug
CQ_INCLUDE_TRYBOTS=tryserver.v8:v8_linux_noi18n_rel_ng

Review-Url: https://codereview.chromium.org/1985423003
Cr-Commit-Position: refs/heads/master@{#36420}

src/js/i18n.js

@@ -1991,6 +1991,23 @@ var defaultObjects = {
   '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.
@@ -1999,6 +2016,7 @@ var defaultObjects = {
 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);
     }

src/runtime/runtime-i18n.cc

@@ -1145,6 +1145,23 @@ RUNTIME_FUNCTION(Runtime_StringLocaleConvertCase) {
                            reinterpret_cast<const char*>(lang_str));
 }
 
+RUNTIME_FUNCTION(Runtime_DateCacheVersion) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(0, args.length());
+  if (isolate->serializer_enabled()) return isolate->heap()->undefined_value();
+  if (!isolate->eternal_handles()->Exists(EternalHandles::DATE_CACHE_VERSION)) {
+    Handle<FixedArray> date_cache_version =
+        isolate->factory()->NewFixedArray(1, TENURED);
+    date_cache_version->set(0, Smi::FromInt(0));
+    isolate->eternal_handles()->CreateSingleton(
+        isolate, *date_cache_version, EternalHandles::DATE_CACHE_VERSION);
+  }
+  Handle<FixedArray> date_cache_version =
+      Handle<FixedArray>::cast(isolate->eternal_handles()->GetSingleton(
+          EternalHandles::DATE_CACHE_VERSION));
+  return date_cache_version->get(0);
+}
+
 }  // namespace internal
 }  // namespace v8
 

src/runtime/runtime.h

@@ -261,7 +261,8 @@ namespace internal {
   F(BreakIteratorBreakType, 1, 1)            \
   F(StringToLowerCaseI18N, 1, 1)             \
   F(StringToUpperCaseI18N, 1, 1)             \
-  F(StringLocaleConvertCase, 3, 1)
+  F(StringLocaleConvertCase, 3, 1)           \
+  F(DateCacheVersion, 0, 1)
 #else
 #define FOR_EACH_INTRINSIC_I18N(F)
 #endif

test/cctest/test-date.cc

@@ -166,3 +166,26 @@ TEST(DaylightSavingsTime) {
   CheckDST(august_20 + 2 * 3600 - 1000);
   CheckDST(august_20);
 }
+
+#ifdef V8_I18N_SUPPORT
+TEST(DateCacheVersion) {
+  FLAG_allow_natives_syntax = true;
+  v8::Isolate* isolate = CcTest::isolate();
+  v8::Isolate::Scope isolate_scope(isolate);
+  v8::HandleScope scope(isolate);
+  v8::Local<v8::Context> context = v8::Context::New(isolate);
+  v8::Context::Scope context_scope(context);
+  v8::Local<v8::Number> date_cache_version =
+      v8::Local<v8::Number>::Cast(CompileRun("%DateCacheVersion()"));
+
+  CHECK(date_cache_version->IsNumber());
+  CHECK_EQ(0.0, date_cache_version->NumberValue(context).FromMaybe(-1.0));
+
+  v8::Date::DateTimeConfigurationChangeNotification(isolate);
+
+  date_cache_version =
+      v8::Local<v8::Number>::Cast(CompileRun("%DateCacheVersion()"));
+  CHECK(date_cache_version->IsNumber());
+  CHECK_EQ(1.0, date_cache_version->NumberValue(context).FromMaybe(-1.0));
+}
+#endif  // V8_I18N_SUPPORT