SkTime: return timezone information

src/ports/SkTime_Unix.cpp

Index: src/ports/SkTime_Unix.cpp
diff --git a/src/ports/SkTime_Unix.cpp b/src/ports/SkTime_Unix.cpp
index 6e305a16f6eb8073e393e1d5d8629826035daaab..2d5fa279b468152cdbd8249764e0a6c29c73fd1f 100644
--- a/src/ports/SkTime_Unix.cpp
+++ b/src/ports/SkTime_Unix.cpp
@@ -16,11 +16,15 @@ void SkTime::GetDateTime(DateTime* dt)
 {
     if (dt)
     {
+        tzset();  // initialize timezone variable;
         time_t m_time;
         time(&m_time);
         struct tm* tstruct;
         tstruct = localtime(&m_time);
+        int offset = tstruct->tm_isdst == 1 ? 60 : 0;
+
         // http://pubs.opengroup.org/onlinepubs/009695399/basedefs/time.h.html
+        dt->fTimeZoneMinutes = SkToS16(offset - timezone / 60);
         dt->fYear       = tstruct->tm_year + 1900;
         dt->fMonth      = SkToU8(tstruct->tm_mon + 1);
         dt->fDayOfWeek  = SkToU8(tstruct->tm_wday);