Disable VirtualAlloc randomization on 32-bit Windows hosts

Disable VirtualAlloc randomization on 32-bit Windows hosts

ASLR is much weaker in a 2GB address space. Plus the vast
majority of 32-bit Windows hosts are XP, which don't have
ASLR anyway. So, avoid the fragmentation and skip it in
this case.

BUG=chromium:394591
LOG=Y
R=jochen@chromium.org

Committed: https://crrev.com/a15c5c96676738dac97f47e0f996b1ada9af3405
Cr-Commit-Position: refs/heads/master@{#31127}

[jschuh, 2015-10-05 19:06:26]

PTAL. I have the following moral equivalent CL on the blink side:
https://codereview.chromium.org/1383153002

[titzer, 2015-10-06 16:31:22]

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

[titzer, 2015-10-06 16:31:22]

lgtm

[jschuh, 2015-10-06 16:35:28]

The CQ bit was checked by jschuh@chromium.org

[commit-bot: I haz the power, 2015-10-06 16:35:34]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1385023002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1385023002/1

[commit-bot: I haz the power, 2015-10-06 16:57:43]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-06 16:58:08]

Patchset 1 (id:??) landed as
https://crrev.com/a15c5c96676738dac97f47e0f996b1ada9af3405
Cr-Commit-Position: refs/heads/master@{#31127}