Forcibly terminate the metro viewer

Forcibly terminate the metro viewer

On trybots, the viewer shutdown is frequently taking 16s, making ash_unittests
as a whole take ~20m. Killing the viewer more aggressively makes all the tests
run at the "normal" time in the 1-500ms range, dropping total time to 5-6m.

R=cpu@chromium.org
BUG=411147
Committed: https://crrev.com/921a7f3597fbab7c94e82910bf9e7c40616b44e0
Cr-Commit-Position: refs/heads/master@{#295749}

[scottmg, 2014-09-19 04:23:01]

scottmg@chromium.org changed reviewers:
+ cpu@chromium.org

[cpu_(ooo_6.6-7.5), 2014-09-19 18:17:45]

lgtm

[cpu_(ooo_6.6-7.5), 2014-09-19 18:17:49]

The CQ bit was checked by cpu@chromium.org

[commit-bot: I haz the power, 2014-09-19 18:18:33]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/584513004/150001

[scottmg, 2014-09-19 18:42:13]

The CQ bit was unchecked by scottmg@chromium.org

[scottmg, 2014-09-19 18:44:04]

The CQ bit was checked by scottmg@chromium.org

[commit-bot: I haz the power, 2014-09-19 18:45:12]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/584513004/150001

[commit-bot: I haz the power, 2014-09-19 18:47:50]

Committed patchset #9 (id:150001) as e793e9c1124aa1fd6f5b260f6d91b951c234283a

[commit-bot: I haz the power, 2014-09-19 18:49:27]

Patchset 9 (id:??) landed as
https://crrev.com/921a7f3597fbab7c94e82910bf9e7c40616b44e0
Cr-Commit-Position: refs/heads/master@{#295749}