tree 4f2afe09cb7ef601d84be9fa33835495286d60ab
parent 7086cfcae53d483d858dca38f37ac54c95719de7
author Kenny Root <kroot@google.com> 1425513696 -0800
committer Kenny Root <kroot@google.com> 1425517537 -0800

Use libmingwex for gmtime_s

gmtime_s first appeared in MSVCR80, but libmingwex has a helper
function that tries to find the symbol or falls back to an internal
implementation.

Change-Id: I5bc27e1cfcc208eb9ea1159d47791fcc90bc7794