Add DCHECK_GT macro.

Add DCHECK_GT macro.

R=ulan@chromium.org
BUG=

Committed: https://crrev.com/3e19476f28f3c86fa48fe4bf945def41f6cd0cf8
Cr-Commit-Position: refs/heads/master@{#31071}

[Michael Lippautz, 2015-10-01 16:51:30]

PTAL

[Michael Lippautz, 2015-10-01 16:54:09]

The CQ bit was checked by mlippautz@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-10-01 16:54:19]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1384453005/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1384453005/1

[commit-bot: I haz the power, 2015-10-01 17:19:21]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-10-01 17:19:22]

Dry run: This issue passed the CQ dry run.

[ulan, 2015-10-02 12:06:53]

lgtm

[Michael Lippautz, 2015-10-02 12:07:01]

The CQ bit was checked by mlippautz@chromium.org

[commit-bot: I haz the power, 2015-10-02 12:07:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1384453005/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1384453005/1

[commit-bot: I haz the power, 2015-10-02 12:08:50]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-02 12:08:58]

Patchset 1 (id:??) landed as
https://crrev.com/3e19476f28f3c86fa48fe4bf945def41f6cd0cf8
Cr-Commit-Position: refs/heads/master@{#31071}