Remove unused macros from config.h

Remove unused macros from config.h.

HAVE_SIGNAL_H, HAVE_TM_GMTOFF, HAVE_TM_ZONE and HAVE_TIMEGM macros are no longer used; so remove them.

HAVE_SYS_TIME_H has been only used in DateMath.cpp, but in other parts of blink we use !OS(WIN) to guard including <sys/time.h>, so lets do the same in DateMath.cpp as well.

Committed: https://crrev.com/7cdc11ff21e6c0f6068510bf72c65ac125a73412
Cr-Commit-Position: refs/heads/master@{#351079}

[lgombos, 2015-09-28 01:07:11]

l.gombos@samsung.com changed reviewers:
+ jochen@chromium.org

[lgombos, 2015-09-28 01:07:12]

Trivial cleanup. The less global macros we have in blink, the better.

[jochen (gone - plz use gerrit), 2015-09-28 11:31:30]

lgtm

[lgombos, 2015-09-28 14:40:50]

The CQ bit was checked by l.gombos@samsung.com

[commit-bot: I haz the power, 2015-09-28 14:41:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1369133002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1369133002/1

[commit-bot: I haz the power, 2015-09-28 16:13:13]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-28 16:14:25]

Patchset 1 (id:??) landed as
https://crrev.com/7cdc11ff21e6c0f6068510bf72c65ac125a73412
Cr-Commit-Position: refs/heads/master@{#351079}