Import of CCTZ from GitHub.

PiperOrigin-RevId: 485054062
Change-Id: Ieafa217b562548f8bb8dc6fc4e1e414f8ede0579

absl/time/internal/cctz/src/time_zone_info.cc

@@ -533,8 +533,8 @@ bool TimeZoneInfo::Load(ZoneInfoSource* zip) {
 
   // Trim redundant transitions. zic may have added these to work around
   // differences between the glibc and reference implementations (see
-  // zic.c:dontmerge) and the Qt library (see zic.c:WORK_AROUND_QTBUG_53071).
-  // For us, they just get in the way when we do future_spec_ extension.
+  // zic.c:dontmerge) or to avoid bugs in old readers. For us, they just
+  // get in the way when we do future_spec_ extension.
   while (hdr.timecnt > 1) {
     if (!EquivTransitions(transitions_[hdr.timecnt - 1].type_index,
                           transitions_[hdr.timecnt - 2].type_index)) {

absl/time/internal/cctz/testdata/version

@@ -1 +1 @@
-2022e
+2022f

absl/time/internal/cctz/testdata/zoneinfo/zone1970.tab

@@ -102,12 +102,9 @@ CA	+4612-05957	America/Glace_Bay	Atlantic - NS (Cape Breton)
 CA	+4606-06447	America/Moncton	Atlantic - New Brunswick
 CA	+5320-06025	America/Goose_Bay	Atlantic - Labrador (most areas)
 CA,BS	+4339-07923	America/Toronto	Eastern - ON, QC (most areas), Bahamas
-CA	+4901-08816	America/Nipigon	Eastern - ON, QC (no DST 1967-73)
-CA	+4823-08915	America/Thunder_Bay	Eastern - ON (Thunder Bay)
 CA	+6344-06828	America/Iqaluit	Eastern - NU (most east areas)
 CA	+6608-06544	America/Pangnirtung	Eastern - NU (Pangnirtung)
 CA	+4953-09709	America/Winnipeg	Central - ON (west); Manitoba
-CA	+4843-09434	America/Rainy_River	Central - ON (Rainy R, Ft Frances)
 CA	+744144-0944945	America/Resolute	Central - NU (Resolute)
 CA	+624900-0920459	America/Rankin_Inlet	Central - NU (central)
 CA	+5024-10439	America/Regina	CST - SK (most areas)