Update clang_win to latest used by Chromium.

Revision number comes from
https://cs.chromium.org/chromium/src/tools/clang/scripts/update.py?l=30&rcl=d8897aff36aefd9ac967d76810057482c5afc0f3
(via mtklein).

This CL is effectively a reland of
https://skia-review.googlesource.com/c/skia/+/114093, using the version
of Clang from the link above as of 2018-03-16. The original CL was
reverted due to skia:7720, which was tangential.

Change-Id: I2a0074a4de26ae8f657d0bce29189b161e20eb66
Reviewed-on: https://skia-review.googlesource.com/115164
Commit-Queue: Ben Wagner <benjaminwagner@google.com>
Reviewed-by: Mike Klein <mtklein@chromium.org>
3 files changed