[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 e89175a37db11aa6990888e26e6bb989cf7c36b5..46df4fa47d2fa20c1e60b30a81364f32ed3b75f4 100644
--- a/src/runtime/runtime-i18n.cc
+++ b/src/runtime/runtime-i18n.cc
@@ -552,6 +552,28 @@ 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));

[jungshik at Google, 2017/03/21 20:29:34]

JFYI: I tried to avoid this pattern ( see lines 417 ~ 430 in the RHS of 
https://codereview.chromium.org/1991753002/diff/20001/src/runtime/runtime-i18...
), but I guess it does not matter much. 

[Dan Ehrenberg, 2017/04/07 11:34:00]

What's the right way to avoid it when constructing a UChar* ? If the input is a
char *, should I be passing in a Latin1 UConverter to the UnicodeString
converter?

I added a TODO here. Mind if it's left for a future patch?

+  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.getTerminatedBuffer()), &status_digits);

[jungshik at Google, 2017/03/21 20:29:35]

You meant currency_icu here? It seems that it's a typo from PS #5 => PS #6. PS
#5 does not have this typo. :-)

[Dan Ehrenberg, 2017/04/07 11:34:00]

Oops, fixed

+#else
+  uint32_t fraction_digits = ucurr_getDefaultFractionDigits(
+      currency.getTerminatedBuffer(), &status_digits);

[jungshik at Google, 2017/03/21 20:29:35]

same here..

It's a pity that  ucurr_getDefaultFractionDigits takes UChar* for something that
is always ASCII. It could have just taken 'char*'. 
Alternatively, if there were a C++ API, you'd not have to do U_ICU_VERSION...
either. 

+#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);