TexSubImage2D no longer needs to match the type in ES3.

TexSubImage2D no longer needs to match the type in ES3.

Texture::ValidForTexture really should not validate type match. Most
times it's no op, and one time it's duplicated effort (TexSubImage2D in
ES2) and generating wrong error (INVALID_VALUE instead of INVALID_OPERATION).

BUG=532708, 429053
TEST=gpu_unittests
R=piman@chromium.org

Committed: https://crrev.com/f9139ed3a1388d7b91ba121aee02e94cf39c66d6
Cr-Commit-Position: refs/heads/master@{#349585}

[Zhenyao Mo, 2015-09-18 00:14:23]

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

[Zhenyao Mo, 2015-09-18 00:15:05]

piman: PTAL
Others: FYI

[commit-bot: I haz the power, 2015-09-18 00:15:25]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1344373004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1344373004/1

[piman, 2015-09-18 00:51:14]

LGTM.

I'm not even convinced the type check is needed for TexSubImage2D in ES2 per
spec, which describes the internal storage in section "3.6.2 Transfer of Pixel
Rectangles", in terms floating point (making TexSubImage2D with mismatching type
well-defined), and nothing in the TexSubImage2D mentions anything specific about
type (it says that format still needs to match the internalformat of the image).

[Zhenyao Mo, 2015-09-18 00:54:08]

I agree.  I looked at the log blame and this was added in 2011 without much
explanation.  It might just be a mis-reading of the spec.

Unfortunately we explicitly add this constraints in WebGL 1 spec (kbr and I
searched and we can't find the motivation why it's added).

Still, we might be able to lift this on the command buffer side.

[commit-bot: I haz the power, 2015-09-18 02:16:49]

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

[commit-bot: I haz the power, 2015-09-18 02:16:50]

Dry run: This issue passed the CQ dry run.

[Zhenyao Mo, 2015-09-18 02:18:46]

The CQ bit was checked by zmo@chromium.org

[commit-bot: I haz the power, 2015-09-18 02:19:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1344373004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1344373004/1

[commit-bot: I haz the power, 2015-09-18 02:24:28]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-18 02:25:13]

Patchset 1 (id:??) landed as
https://crrev.com/f9139ed3a1388d7b91ba121aee02e94cf39c66d6
Cr-Commit-Position: refs/heads/master@{#349585}