[Intl] Reduces memory by sharing code.

Bug: chromium:928098
Change-Id: I47333b06bb7cf2319eec6f6beab830ce6c6da1c5
Reviewed-on: https://chromium-review.googlesource.com/c/1461162Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59474}

src/objects/intl-objects.cc

@@ -29,6 +29,7 @@
 #include "unicode/brkiter.h"
 #include "unicode/calendar.h"
 #include "unicode/coll.h"
+#include "unicode/datefmt.h"
 #include "unicode/decimfmt.h"
 #include "unicode/locid.h"
 #include "unicode/normalizer2.h"
@@ -1859,5 +1860,17 @@ Intl::HourCycle Intl::ToHourCycle(const std::string& hc) {
   return Intl::HourCycle::kUndefined;
 }
 
+const std::set<std::string>& Intl::GetAvailableLocalesForLocale() {
+  static base::LazyInstance<Intl::AvailableLocales<icu::Locale>>::type
+      available_locales = LAZY_INSTANCE_INITIALIZER;
+  return available_locales.Pointer()->Get();
+}
+
+const std::set<std::string>& Intl::GetAvailableLocalesForDateFormat() {
+  static base::LazyInstance<Intl::AvailableLocales<icu::DateFormat>>::type
+      available_locales = LAZY_INSTANCE_INITIALIZER;
+  return available_locales.Pointer()->Get();
+}
+
 }  // namespace internal
 }  // namespace v8

src/objects/intl-objects.h

@@ -291,6 +291,10 @@ class Intl {
   static const uint8_t* ToLatin1LowerTable();
 
   static String ConvertOneByteToLower(String src, String dst);
+
+  static const std::set<std::string>& GetAvailableLocalesForLocale();
+
+  static const std::set<std::string>& GetAvailableLocalesForDateFormat();
 };
 
 }  // namespace internal

src/objects/js-date-time-format.cc

@@ -1508,9 +1508,7 @@ MaybeHandle<Object> JSDateTimeFormat::FormatToParts(
 }
 
 const std::set<std::string>& JSDateTimeFormat::GetAvailableLocales() {
-  static base::LazyInstance<Intl::AvailableLocales<icu::DateFormat>>::type
-      available_locales = LAZY_INSTANCE_INITIALIZER;
-  return available_locales.Pointer()->Get();
+  return Intl::GetAvailableLocalesForDateFormat();
 }
 
 Handle<String> JSDateTimeFormat::HourCycleAsString() const {

src/objects/js-list-format.cc

@@ -412,13 +412,10 @@ MaybeHandle<String> JSListFormat::FormatList(Isolate* isolate,
 }
 
 const std::set<std::string>& JSListFormat::GetAvailableLocales() {
-  // TODO(ftang): for now just use
-  // icu::Locale::getAvailableLocales(count) until we migrate to
-  // Intl::GetAvailableLocales().
+  // Since ListFormatter does not have a method to list all supported
+  // locales, use the one in icu::Locale per comments in
   // ICU FR at https://unicode-org.atlassian.net/browse/ICU-20015
-  static base::LazyInstance<Intl::AvailableLocales<icu::Locale>>::type
-      available_locales = LAZY_INSTANCE_INITIALIZER;
-  return available_locales.Pointer()->Get();
+  return Intl::GetAvailableLocalesForLocale();
 }
 
 // ecma42 #sec-formatlisttoparts

src/objects/js-plural-rules.cc

@@ -320,9 +320,7 @@ const std::set<std::string>& JSPluralRules::GetAvailableLocales() {
   // PluralRules is missing an appropriate getAvailableLocales method,
   // so we should filter from all locales, but it's not clear how; see
   // https://ssl.icu-project.org/trac/ticket/12756
-  static base::LazyInstance<Intl::AvailableLocales<icu::Locale>>::type
-      available_locales = LAZY_INSTANCE_INITIALIZER;
-  return available_locales.Pointer()->Get();
+  return Intl::GetAvailableLocalesForLocale();
 }
 
 }  // namespace internal

src/objects/js-relative-time-format.cc

@@ -18,7 +18,6 @@
 #include "src/objects/intl-objects.h"
 #include "src/objects/js-number-format.h"
 #include "src/objects/js-relative-time-format-inl.h"
-#include "unicode/datefmt.h"
 #include "unicode/numfmt.h"
 #include "unicode/reldatefmt.h"
 
@@ -410,9 +409,9 @@ MaybeHandle<Object> JSRelativeTimeFormat::Format(
 }
 
 const std::set<std::string>& JSRelativeTimeFormat::GetAvailableLocales() {
-  static base::LazyInstance<Intl::AvailableLocales<icu::DateFormat>>::type
-      available_locales = LAZY_INSTANCE_INITIALIZER;
-  return available_locales.Pointer()->Get();
+  // Since RelativeTimeFormatter does not have a method to list all
+  // available locales, work around by calling the DateFormat.
+  return Intl::GetAvailableLocalesForDateFormat();
 }
 
 }  // namespace internal