[intl] Fix NumberFormat options handling spec compliance issues

src/runtime/runtime-i18n.cc

Index: src/runtime/runtime-i18n.cc
diff --git a/src/runtime/runtime-i18n.cc b/src/runtime/runtime-i18n.cc
index 7b5ea181e1368a44cc7b9c205af1909c3e669fb2..80c8a9cd012a89210dfa54accd5a386bd8739a03 100644
--- a/src/runtime/runtime-i18n.cc
+++ b/src/runtime/runtime-i18n.cc
@@ -532,6 +532,29 @@ RUNTIME_FUNCTION(Runtime_InternalNumberFormat) {
                    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);