Bug 1763783 - Part 10: Remove no longer needed workarounds for ICU-21154 and ICU-21155. r=platform-i18n-reviewers,jfkthame

ICU-21154 and ICU-21155 have been fixed in ICU 71, so we can remove this
workaround.

Depends on D143282

Differential Revision: https://phabricator.services.mozilla.com/D143283

intl/components/src/DateTimeFormat.h

@@ -419,8 +419,7 @@ class DateTimeFormat final {
    * plan to remove it.
    */
   template <typename B>
-  ICUResult GetOriginalSkeleton(B& aBuffer,
-                                Maybe<HourCycle> aHourCycle = Nothing()) {
+  ICUResult GetOriginalSkeleton(B& aBuffer) {
     static_assert(std::is_same_v<typename B::CharType, char16_t>);
     if (mOriginalSkeleton.length() == 0) {
       // Generate a skeleton from the resolved pattern, there was no originally
@@ -436,10 +435,6 @@ class DateTimeFormat final {
     if (!FillBuffer(mOriginalSkeleton, aBuffer)) {
       return Err(ICUError::OutOfMemory);
     }
-    if (aHourCycle) {
-      DateTimeFormat::ReplaceHourSymbol(Span(aBuffer.data(), aBuffer.length()),
-                                        *aHourCycle);
-    }
     return Ok();
   }
   /**

js/src/builtin/intl/DateTimeFormat.cpp

@@ -1335,9 +1335,7 @@ static mozilla::intl::DateIntervalFormat* NewDateIntervalFormat(
     return nullptr;
   }
 
-  // Determine the hour cycle used in the resolved pattern. This is needed to
-  // workaround <https://unicode-org.atlassian.net/browse/ICU-21154> and
-  // <https://unicode-org.atlassian.net/browse/ICU-21155>.
+  // Determine the hour cycle used in the resolved pattern.
   mozilla::Maybe<mozilla::intl::DateTimeFormat::HourCycle> hcPattern =
       mozilla::intl::DateTimeFormat::HourCycleFromPattern(pattern);
 
@@ -1357,7 +1355,7 @@ static mozilla::intl::DateIntervalFormat* NewDateIntervalFormat(
   mozilla::Span<const char16_t> timeZoneChars = timeZone.twoByteRange();
 
   FormatBuffer<char16_t, intl::INITIAL_CHAR_BUFFER_SIZE> skeleton(cx);
-  auto skelResult = mozDtf.GetOriginalSkeleton(skeleton, hcPattern);
+  auto skelResult = mozDtf.GetOriginalSkeleton(skeleton);
   if (skelResult.isErr()) {
     intl::ReportInternalError(cx, skelResult.unwrapErr());
     return nullptr;