Add a second unsafe ES3 API in command buffer.

Add a second unsafe ES3 API in command buffer.

glCopuBufferSubData

Also, I disabled validator for unsafe functions.

BUG=429053
TEST=gpu_unittests
R=bajones@chromium.org
TBR=sievers@chromium.org

Committed: https://crrev.com/481d910f1191a34b185e0722a7284cb08503af85
Cr-Commit-Position: refs/heads/master@{#305522}

[Zhenyao Mo, 2014-11-24 18:25:18]

Patchset #1 (id:1) has been deleted

[Zhenyao Mo, 2014-11-24 18:39:11]

zmo@chromium.org changed reviewers:
- kbr@chromium.org

[Zhenyao Mo, 2014-11-24 18:40:57]

bajones: please review.
kbr,vmiura: FYI.

sievers: since the only file that this CL touches that bajones is not a owner is
the auto generated gpu/GLES2/gl2chromium_autogen.h, so I TBR to you.

[bajones, 2014-11-24 18:59:33]

lgtm

[Zhenyao Mo, 2014-11-24 21:22:38]

The CQ bit was checked by zmo@chromium.org

[commit-bot: I haz the power, 2014-11-24 21:23:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/754873002/60001

[commit-bot: I haz the power, 2014-11-24 23:52:45]

Committed patchset #3 (id:60001)

[commit-bot: I haz the power, 2014-11-24 23:53:27]

Patchset 3 (id:??) landed as
https://crrev.com/481d910f1191a34b185e0722a7284cb08503af85
Cr-Commit-Position: refs/heads/master@{#305522}