Revert "[Intl] Use new getDefaultHourCycle to replace old hack"

This reverts commit 611e4127.

Reason for revert: https://crbug.com/1080367

Original change's description:
> [Intl] Use new getDefaultHourCycle to replace old hack
> 
> Use the ICU 67.1 new API DateTimePatternGenerator::getDefaultHourCycle
> to replace a hack which get the pattern of "jjmm" to find out the
> default hour cycle of a locale
> Bump the required API version from 65 to 67
> 
> Bug: v8:10225
> Change-Id: I3378edacb6dfb8400357ac0bf3d5d50b9fe008bd
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2173875
> Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
> Commit-Queue: Frank Tang <ftang@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#67549}

TBR=jkummerow@chromium.org,ftang@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: v8:10225
Change-Id: I8bdfbdfc6c906814e5a7525cbde79c9cac854bd1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2208811Reviewed-by: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67929}

src/objects/intl-objects.h

@@ -21,7 +21,7 @@
 #include "unicode/locid.h"
 #include "unicode/uversion.h"
 
-#define V8_MINIMUM_ICU_VERSION 67
+#define V8_MINIMUM_ICU_VERSION 65
 
 namespace U_ICU_NAMESPACE {
 class BreakIterator;

src/objects/js-date-time-format.cc

@@ -59,21 +59,6 @@ JSDateTimeFormat::HourCycle ToHourCycle(const std::string& hc) {
   return JSDateTimeFormat::HourCycle::kUndefined;
 }
 
-JSDateTimeFormat::HourCycle ToHourCycle(UDateFormatHourCycle hc) {
-  switch (hc) {
-    case UDAT_HOUR_CYCLE_11:
-      return JSDateTimeFormat::HourCycle::kH11;
-    case UDAT_HOUR_CYCLE_12:
-      return JSDateTimeFormat::HourCycle::kH12;
-    case UDAT_HOUR_CYCLE_23:
-      return JSDateTimeFormat::HourCycle::kH23;
-    case UDAT_HOUR_CYCLE_24:
-      return JSDateTimeFormat::HourCycle::kH24;
-    default:
-      return JSDateTimeFormat::HourCycle::kUndefined;
-  }
-}
-
 Maybe<JSDateTimeFormat::HourCycle> GetHourCycle(Isolate* isolate,
                                                 Handle<JSReceiver> options,
                                                 const char* method) {
@@ -1558,8 +1543,9 @@ MaybeHandle<JSDateTimeFormat> JSDateTimeFormat::New(
       generator_cache.Pointer()->CreateGenerator(icu_locale));
 
   // 15.Let hcDefault be dataLocaleData.[[hourCycle]].
-  HourCycle hc_default = ToHourCycle(generator->getDefaultHourCycle(status));
+  icu::UnicodeString hour_pattern = generator->getBestPattern("jjmm", status);
   CHECK(U_SUCCESS(status));
+  HourCycle hc_default = HourCycleFromPattern(hour_pattern);
 
   // 16.Let hc be r.[[hc]].
   HourCycle hc = HourCycle::kUndefined;