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..54acba5a23d285dcd8cfa593995019b4f759572c 100644
--- a/src/ports/SkTime_Unix.cpp
+++ b/src/ports/SkTime_Unix.cpp
@@ -16,10 +16,13 @@ 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->fYear       = tstruct->tm_year + 1900;
         dt->fMonth      = SkToU8(tstruct->tm_mon + 1);
@@ -28,6 +31,7 @@ void SkTime::GetDateTime(DateTime* dt)
         dt->fHour       = SkToU8(tstruct->tm_hour);
         dt->fMinute     = SkToU8(tstruct->tm_min);
         dt->fSecond     = SkToU8(tstruct->tm_sec);
+        dt->fTimeZoneMinutes = SkToS16(offset - timezone / 60);
     }
 }