[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 0b45381914641a824e36e99eaa0d315bf96252aa..df60891c2527ad9b8c83c0654ef1f3070ce33794 100644
--- a/src/runtime/runtime-i18n.cc
+++ b/src/runtime/runtime-i18n.cc
@@ -551,6 +551,25 @@ RUNTIME_FUNCTION(Runtime_InternalNumberFormat) {
                    result.length())));
 }
 
+RUNTIME_FUNCTION(Runtime_CurrencyDigits) {
+  DCHECK_EQ(1, args.length());
+
+  CONVERT_ARG_HANDLE_CHECKED(String, currency, 0);
+
+  v8::String::Utf8Value currency_string(v8::Utils::ToLocal(currency));
+  icu::UnicodeString currency_icu =
+      icu::UnicodeString::fromUTF8(*currency_string);

[Dan Ehrenberg, 2017/02/24 19:51:21]

Yes, this is a terrible way to get a UnicodeString from a V8 string, but this
one needs to be null-terminated, and I'm following the way that's done in the
rest of the file. A cleanup for all of these usage sites should come in a
follow-on patch.

+
+  {
+    DisallowHeapAllocation no_gc;
+    UErrorCode status = U_ZERO_ERROR;
+    uint32_t fraction_digits = ucurr_getDefaultFractionDigits(
+        currency_icu.getTerminatedBuffer(), &status);
+    // 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);