clang/win: Turn off Winconsistent-missing-override for now.

clang/win: Turn off Winconsistent-missing-override for now.

We can't fix all instances of this warning at the moment (because of gmock
and because of blink apis, see bug). We've fixed many, but our bots still
show almost 20k warnings due to this warning, most of them in v8. That's already
fixed upstream, but v8 rolls don't happen often. Turn the warning off for now.

BUG=428099
NOTRY=true

Committed: https://crrev.com/42c03079517c6b0ea14b0427ccd276157b1bef45
Cr-Commit-Position: refs/heads/master@{#302356}

[Nico, 2014-10-31 23:32:35]

thakis@chromium.org changed reviewers:
+ rnk@chromium.org

[Reid Kleckner, 2014-10-31 23:50:07]

lgtm

Thanks for investigating the reports!

[Nico, 2014-10-31 23:50:31]

The CQ bit was checked by thakis@chromium.org

[commit-bot: I haz the power, 2014-10-31 23:51:54]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/687343003/1

[commit-bot: I haz the power, 2014-10-31 23:52:35]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-10-31 23:53:19]

Patchset 1 (id:??) landed as
https://crrev.com/42c03079517c6b0ea14b0427ccd276157b1bef45
Cr-Commit-Position: refs/heads/master@{#302356}

[hans, 2014-11-03 12:40:31]

hans@chromium.org changed reviewers:
+ hans@chromium.org

[hans, 2014-11-03 12:40:31]

Users trying to reproduce Win ASan failures locally are now getting build
warnings about unknown option -Wno-inconsistent-missing-override, because they
get an older Clang version (r220557 atm) that doesn't have that flag :/

Timur: maybe we can just bump the Win-ASan version to fix this?