Make GetDefaultThreadStackSize() return 16M under ThreadSanitizer

Make GetDefaultThreadStackSize() return 16M under ThreadSanitizer
This should help some browser tests that are currently hitting the roof under TSan.

BUG=335516
R=epenner@chromium.org,dvyukov@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=246280

[Alexander Potapenko, 2014-01-21 08:19:19]

Eric, Dima, could you please take a look? Thanks.

[Dmitry Vyukov, 2014-01-21 08:45:08]

LGTM

[Alexander Potapenko, 2014-01-21 10:07:03]

+Nico as a base/ owner

[Alexander Potapenko, 2014-01-21 10:07:25]

On 2014/01/21 10:07:03, Alexander Potapenko wrote:
> +Nico as a base/ owner

s/Nico/Nico

[Nico, 2014-01-21 20:05:43]

lgtm

Now deep recursion will die earlier under tsan, but I guess we don't like deep
recursion anyhow.

[epennerAtGoogle, 2014-01-21 20:10:03]

On 2014/01/21 20:05:43, Nico wrote:
> lgtm
> 
> Now deep recursion will die earlier under tsan, but I guess we don't like deep
> recursion anyhow.

LGTM

On a tangent, does anyone know how to see what our high-water-mark stack usage
is on a thread? My understanding is that the default stack allocation is only
counted as address space until it is actually used, after which it adds
permanently to real memory usage...

With many many threads at a 1MB default, I'm just wondering how much of that
ends up getting used.

[Alexander Potapenko, 2014-01-22 04:30:30]

On 2014/01/21 20:05:43, Nico wrote:
> lgtm
> 
> Now deep recursion will die earlier under tsan, but I guess we don't like deep
> recursion anyhow.

Why should it? I'm increasing the default stack size under TSan.

[commit-bot: I haz the power, 2014-01-22 04:34:00]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/glider@chromium.org/143933002/1

[commit-bot: I haz the power, 2014-01-22 10:43:13]

Change committed as 246280