Roll ICU to 172d331 and use icu tz in wtf

This roll has just one change to fix the timezone
detection on Japanese/Korean and other non-English
Windows.

  https://chromium-review.googlesource.com/1094322

In addition, switch to ICU to convert UTC to local time
in blink. This is to deal with a cryptic failure of
external/wpt/html/dom/doc*/resource*/document-lastModified-01.html

parens.

Bug: 849724
Test: Set the timezone to Tokyo on Japanese Windows
Test: In JS console, 'new Date()' outputs 'Japan Standard Time' in
Test: Layout test external/wpt/html/dom/doc*/resource*/document-lastModified-01.html
Change-Id: I3037252ff9044a114ae831de2b151df7c652603c
Reviewed-on: https://chromium-review.googlesource.com/1100739Reviewed-by: Kent Tamura <tkent@chromium.org>
Commit-Queue: Jungshik Shin <jshin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#569262}

DEPS

@@ -684,7 +684,7 @@ deps = {
     Var('chromium_git') + '/chromium/deps/hunspell_dictionaries.git' + '@' + 'a9bac57ce6c9d390a52ebaad3259f5fdb871210e',
 
   'src/third_party/icu':
-    Var('chromium_git') + '/chromium/deps/icu.git' + '@' + 'f61e46dbee9d539a32551493e3bcc1dea92f83ec',
+    Var('chromium_git') + '/chromium/deps/icu.git' + '@' + '172d33141cd16df9d027cfd49bfe940b1dc66f1a',
 
   'src/third_party/icu4j': {
       'packages': [

third_party/blink/renderer/platform/wtf/date_math.cc

@@ -77,6 +77,7 @@
 #include <time.h>
 #include <algorithm>
 #include <limits>
+#include <memory>
 #include "build/build_config.h"
 #include "third_party/blink/renderer/platform/wtf/ascii_ctype.h"
 #include "third_party/blink/renderer/platform/wtf/assertions.h"
@@ -86,6 +87,8 @@
 #include "third_party/blink/renderer/platform/wtf/text/string_builder.h"
 #include "third_party/blink/renderer/platform/wtf/time.h"
 
+#include <unicode/timezone.h>
+
 #if defined(OS_WIN)
 #include <windows.h>
 #else
@@ -835,9 +838,11 @@ String MakeRFC2822DateString(const Time date, int utc_offset) {
 }
 
 double ConvertToLocalTime(double ms) {
-  double utc_offset = CalculateUTCOffset();
-  double dst_offset = CalculateDSTOffset(ms, utc_offset);
-  return (ms + utc_offset + dst_offset);
+  std::unique_ptr<icu::TimeZone> timezone(icu::TimeZone::createDefault());
+  int32_t raw_offset, dst_offset;
+  UErrorCode status = U_ZERO_ERROR;
+  timezone->getOffset(ms, false, raw_offset, dst_offset, status);
+  return (ms + static_cast<double>(raw_offset + dst_offset));
 }
 
 }  // namespace WTF