Export of internal Abseil changes.

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855576faf9556573fd74c2874b290d8feb6565d5 by Gennadiy Rozental <rogeeff@google.com>:

Import of CCTZ from GitHub.

PiperOrigin-RevId: 241395451

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b93bfd43eb2a992258f131e10f503526cfec6d48 by CJ Johnson <johnsoncj@google.com>:

Fixes comment over AbslHashValue for InlinedVector

PiperOrigin-RevId: 241368320

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75f58dafcac7d78c28d92a61ec7e53c5b3b86697 by Matt Kulukundis <kfm@google.com>:

Do not call sampling logic for tables with custom allocators.

PiperOrigin-RevId: 241356451

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09f1b4889476ff707a54189aff540e2fe1edcf61 by Derek Mauro <dmauro@google.com>:

Re-enable optionalTest.InPlaceTSFINAEBug after libc++ update

PiperOrigin-RevId: 241222673

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01a8bb5a8cb1e13e88ddb92f9c0160beb6e126be by Derek Mauro <dmauro@google.com>:

Update Clang on Kokoro to r356196.

This includes a workaround for a -Wgnu-include-next warning fixed by
https://reviews.llvm.org/rG0706e144d57305782988dd4367530ae04986116f

PiperOrigin-RevId: 241222395

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1de66bb669a7ec1494d6064677687f761ee2d369 by Abseil Team <absl-team@google.com>:

Remove identical test and fix char to string per comment

PiperOrigin-RevId: 240855512
GitOrigin-RevId: 855576faf9556573fd74c2874b290d8feb6565d5
Change-Id: Ie155b209ef5567e6597da6ef1844db7e2ad72586

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

@@ -23,6 +23,7 @@
 
 #if defined(__APPLE__)
 #include <CoreFoundation/CFTimeZone.h>
+#include <vector>
 #endif
 
 #include <cstdlib>
@@ -121,24 +122,32 @@ time_zone fixed_time_zone(const seconds& offset) {
 
 time_zone local_time_zone() {
   const char* zone = ":localtime";
+#if defined(__ANDROID__)
+  char sysprop[PROP_VALUE_MAX];
+  if (__system_property_get("persist.sys.timezone", sysprop) > 0) {
+    zone = sysprop;
+  }
+#endif
+#if defined(__APPLE__)
+  std::vector<char> buffer;
+  CFTimeZoneRef tz_default = CFTimeZoneCopyDefault();
+  if (CFStringRef tz_name = CFTimeZoneGetName(tz_default)) {
+    CFStringEncoding encoding = kCFStringEncodingUTF8;
+    CFIndex length = CFStringGetLength(tz_name);
+    buffer.resize(CFStringGetMaximumSizeForEncoding(length, encoding) + 1);
+    if (CFStringGetCString(tz_name, &buffer[0], buffer.size(), encoding)) {
+      zone = &buffer[0];
+    }
+  }
+  CFRelease(tz_default);
+#endif
 
   // Allow ${TZ} to override to default zone.
   char* tz_env = nullptr;
 #if defined(_MSC_VER)
   _dupenv_s(&tz_env, nullptr, "TZ");
-#elif defined(__APPLE__)
-  CFTimeZoneRef system_time_zone = CFTimeZoneCopyDefault();
-  CFStringRef tz_name = CFTimeZoneGetName(system_time_zone);
-  tz_env = strdup(CFStringGetCStringPtr(tz_name, CFStringGetSystemEncoding()));
-  CFRelease(system_time_zone);
 #else
   tz_env = std::getenv("TZ");
-#endif
-#if defined(__ANDROID__)
-  char sysprop[PROP_VALUE_MAX];
-  if (tz_env == nullptr)
-    if (__system_property_get("persist.sys.timezone", sysprop) > 0)
-      tz_env = sysprop;
 #endif
   if (tz_env) zone = tz_env;
 
@@ -163,8 +172,6 @@ time_zone local_time_zone() {
 #if defined(_MSC_VER)
   free(localtime_env);
   free(tz_env);
-#elif defined(__APPLE__)
-  free(tz_env);
 #endif
 
   time_zone tz;

absl/time/internal/cctz/src/tzfile.h

@@ -33,6 +33,9 @@
 #define TZDEFRULES	"posixrules"
 #endif /* !defined TZDEFRULES */
 
+
+/* See Internet RFC 8536 for more details about the following format.  */
+
 /*
 ** Each file begins with. . .
 */

absl/time/internal/cctz/testdata/version

@@ -1 +1 @@
-2018i
+2019a

absl/time/internal/cctz/testdata/zoneinfo/iso3166.tab

@@ -9,7 +9,7 @@
 # All text uses UTF-8 encoding.  The columns of the table are as follows:
 #
 # 1.  ISO 3166-1 alpha-2 country code, current as of
-#     ISO 3166-1 N905 (2016-11-15).  See: Updates on ISO 3166-1
+#     ISO 3166-1 N976 (2018-11-06).  See: Updates on ISO 3166-1
 #     https://isotc.iso.org/livelink/livelink/Open/16944257
 # 2.  The usual English name for the coded region,
 #     chosen so that alphabetic sorting of subsets produces helpful lists.
@@ -166,7 +166,7 @@ ME	Montenegro
 MF	St Martin (French)
 MG	Madagascar
 MH	Marshall Islands
-MK	Macedonia
+MK	North Macedonia
 ML	Mali
 MM	Myanmar (Burma)
 MN	Mongolia
@@ -235,7 +235,7 @@ ST	Sao Tome & Principe
 SV	El Salvador
 SX	St Maarten (Dutch)
 SY	Syria
-SZ	Swaziland
+SZ	Eswatini (Swaziland)
 TC	Turks & Caicos Is
 TD	Chad
 TF	French Southern & Antarctic Lands