Add UniformBlocks related commands to command buffer.

Add UniformBlock related commands to command buffer.

1) glGetUniformBlocksCHROMIUM

This is Chromium GPU command buffer internal command. The purpose is to
fetch UniformBlock related information in a linked program from service side
in one command instead of multiple ones.

2) glGetUniformBlockIndex
3) glGetActiveUniformBlockName

Get value from client side cache (retrieved by GetUniformBlockCHROMIUM);
if that fails, send the command to service side.

What's missing: glGetActiveUniformBlockiv.  It requires some extra tuning, so
leave that for a separate CL.

BUG=453127, 429053
TEST=gpu_unittests
R=piman@chromium.org

Committed: https://crrev.com/4a16ff998e64bf2aa245339035acdf9a05819c9d
Cr-Commit-Position: refs/heads/master@{#314897}

[Zhenyao Mo, 2015-02-04 17:24:59]

Patchset #1 (id:1) has been deleted

[Zhenyao Mo, 2015-02-04 17:25:08]

Patchset #1 (id:20001) has been deleted

[Zhenyao Mo, 2015-02-04 17:25:16]

Patchset #1 (id:40001) has been deleted

[Zhenyao Mo, 2015-02-04 19:15:30]

Patchset #2 (id:80001) has been deleted

[Zhenyao Mo, 2015-02-04 23:00:23]

Patchset #3 (id:120001) has been deleted

[Zhenyao Mo, 2015-02-04 23:32:56]

Patchset #4 (id:160001) has been deleted

[Zhenyao Mo, 2015-02-04 23:38:10]

Patchset #4 (id:180001) has been deleted

[Zhenyao Mo, 2015-02-05 18:38:27]

Patchset #6 (id:240001) has been deleted

[Zhenyao Mo, 2015-02-05 18:38:38]

Patchset #5 (id:220001) has been deleted

[Zhenyao Mo, 2015-02-05 18:38:46]

Patchset #4 (id:200001) has been deleted

[Zhenyao Mo, 2015-02-05 19:28:35]

piman: please review.
Others: FYI (feel free to review.)

[piman, 2015-02-05 21:51:59]

lgtm

[Zhenyao Mo, 2015-02-05 22:13:10]

The CQ bit was checked by zmo@chromium.org

[commit-bot: I haz the power, 2015-02-05 22:13:57]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/895933004/280001

[commit-bot: I haz the power, 2015-02-05 22:19:13]

Committed patchset #5 (id:280001)

[commit-bot: I haz the power, 2015-02-05 22:20:07]

Patchset 5 (id:??) landed as
https://crrev.com/4a16ff998e64bf2aa245339035acdf9a05819c9d
Cr-Commit-Position: refs/heads/master@{#314897}