Prepare for ICU's switch to char16_t

ICU's UChar was uint16_t (non-Win) or wchar_t (Windows). It's switching
to char16_t in both C/C++ API. It needs some changes. Fortunately,
v8 needs only a couple of changes because v8 has been using
reinterpret_cast in many places calling ICU API.

This change was confirmed to work fine with ICU-59-to-be.

BUG=v8:6062
TEST=trybot

Review-Url: https://codereview.chromium.org/2738503008
Cr-Commit-Position: refs/heads/master@{#43707}

src/i18n.cc

@@ -30,8 +30,13 @@
 #include "unicode/ucol.h"
 #include "unicode/ucurr.h"
 #include "unicode/unum.h"
+#include "unicode/uvernum.h"
 #include "unicode/uversion.h"
 
+#if U_ICU_VERSION_MAJOR_NUM >= 59
+#include "unicode/char16ptr.h"
+#endif
+
 namespace v8 {
 namespace internal {
 
@@ -270,8 +275,13 @@ icu::DecimalFormat* CreateICUNumberFormat(
       }
 
       UErrorCode status_digits = U_ZERO_ERROR;
+#if U_ICU_VERSION_MAJOR_NUM >= 59
       uint32_t fraction_digits = ucurr_getDefaultFractionDigits(
-        currency.getTerminatedBuffer(), &status_digits);
+          icu::toUCharPtr(currency.getTerminatedBuffer()), &status_digits);
+#else
+      uint32_t fraction_digits = ucurr_getDefaultFractionDigits(
+          currency.getTerminatedBuffer(), &status_digits);
+#endif
       if (U_SUCCESS(status_digits)) {
         number_format->setMinimumFractionDigits(fraction_digits);
         number_format->setMaximumFractionDigits(fraction_digits);

src/runtime/runtime-i18n.cc

@@ -43,6 +43,7 @@
 #include "unicode/uloc.h"
 #include "unicode/unistr.h"
 #include "unicode/unum.h"
+#include "unicode/ustring.h"
 #include "unicode/uversion.h"
 
 
@@ -609,10 +610,11 @@ RUNTIME_FUNCTION(Runtime_InternalCompare) {
     String::FlatContent flat2 = string2->GetFlatContent();
     std::unique_ptr<uc16[]> sap1;
     std::unique_ptr<uc16[]> sap2;
-    const UChar* string_val1 = GetUCharBufferFromFlat(flat1, &sap1, length1);
-    const UChar* string_val2 = GetUCharBufferFromFlat(flat2, &sap2, length2);
-    result =
-        collator->compare(string_val1, length1, string_val2, length2, status);
+    icu::UnicodeString string_val1(
+        FALSE, GetUCharBufferFromFlat(flat1, &sap1, length1), length1);
+    icu::UnicodeString string_val2(
+        FALSE, GetUCharBufferFromFlat(flat2, &sap2, length2), length2);
+    result = collator->compare(string_val1, string_val2, status);
   }
   if (U_FAILURE(status)) return isolate->ThrowIllegalOperation();