[intl] Fix NumberFormat options handling spec compliance issues

src/runtime/runtime-i18n.cc

 // Copyright 2014 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.
 
 
 #ifdef V8_I18N_SUPPORT
 #include "src/runtime/runtime-utils.h"
 
 #include <memory>
 
@@ skipping 514 matching lines @@
 
   icu::UnicodeString result;
   number_format->format(value->Number(), result);
 
   RETURN_RESULT_OR_FAILURE(
       isolate, isolate->factory()->NewStringFromTwoByte(Vector<const uint16_t>(
                    reinterpret_cast<const uint16_t*>(result.getBuffer()),
                    result.length())));
 }
 
+RUNTIME_FUNCTION(Runtime_CurrencyDigits) {
+  DCHECK_EQ(1, args.length());
+
+  CONVERT_ARG_HANDLE_CHECKED(String, currency, 0);
+
+  // TODO(littledan): Avoid transcoding the string twice
+  v8::String::Utf8Value currency_string(v8::Utils::ToLocal(currency));
+  icu::UnicodeString currency_icu =
+      icu::UnicodeString::fromUTF8(*currency_string);
+
+  DisallowHeapAllocation no_gc;
+  UErrorCode status = U_ZERO_ERROR;
+#if U_ICU_VERSION_MAJOR_NUM >= 59
+  uint32_t fraction_digits = ucurr_getDefaultFractionDigits(
+      icu::toUCharPtr(currency_icu.getTerminatedBuffer()), &status);
+#else
+  uint32_t fraction_digits = ucurr_getDefaultFractionDigits(
+      currency_icu.getTerminatedBuffer(), &status);
+#endif
+  // For missing currency codes, default to the most common, 2
+  if (!U_SUCCESS(status)) fraction_digits = 2;
+  return Smi::FromInt(fraction_digits);
+}
 
 RUNTIME_FUNCTION(Runtime_CreateCollator) {
   HandleScope scope(isolate);
 
   DCHECK_EQ(3, args.length());
 
   CONVERT_ARG_HANDLE_CHECKED(String, locale, 0);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, options, 1);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, resolved, 2);
 
@@ skipping 270 matching lines @@
   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
 
 #endif  // V8_I18N_SUPPORT