Revert of [cq] Increase commit burst delay.

Revert of [cq] Increase commit burst delay. (patchset #1 id:1 of https://codereview.chromium.org/1258193003/)

Reason for revert:
Committing more than one CL at a time led to some odd buildbot behavior on the console (probably an independent bug).

Original issue's description:
> [cq] Increase commit burst delay.
>
> TBR=jkummerow@chromium.org, hablich@chromium.org
> NOTRY=true
> NOTREECHECKS=true
>
> Committed: https://crrev.com/1f2e914d103532df410f118c81c60fba8b6a00e0
> Cr-Commit-Position: refs/heads/master@{#29914}

TBR=jkummerow@chromium.org,hablich@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Committed: https://crrev.com/029c8131457d605f559905ede3562c31e2382256
Cr-Commit-Position: refs/heads/master@{#29944}

[Michael Achenbach, 2015-07-31 07:16:11]

Created Revert of [cq] Increase commit burst delay.

[commit-bot: I haz the power, 2015-07-31 07:16:24]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1263183002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1263183002/1

[commit-bot: I haz the power, 2015-07-31 07:16:35]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-07-31 07:17:01]

Patchset 1 (id:??) landed as
https://crrev.com/029c8131457d605f559905ede3562c31e2382256
Cr-Commit-Position: refs/heads/master@{#29944}

[Michael Hablich, 2015-07-31 07:55:29]

On 2015/07/31 07:17:01, commit-bot: I haz the power wrote:
> Patchset 1 (id:??) landed as
> https://crrev.com/029c8131457d605f559905ede3562c31e2382256
> Cr-Commit-Position: refs/heads/master@{#29944}

lgtm