Generate INVALID_OPERATION if feedback loops exist in CopyTex{Sub}Image2D.

Generate INVALID_OPERATION if feedback loops exist in CopyTex{Sub}Image2D.

BUG=421695
TEST=gpu_unittests, webgl_conformance_tests
R=bajones@chromium.org

Committed: https://crrev.com/383512cf52d0c163a3fbbd8e9937b5c3c6d80eda
Cr-Commit-Position: refs/heads/master@{#299399}

[Zhenyao Mo, 2014-10-13 22:15:06]

bajones: please review.

Tested with WebGL conformance tests on linux NVIDIA.

With this CL, no regression, and
https://www.khronos.org/registry/webgl/sdk/tests/conformance/textures/texture...
passes.

[bajones, 2014-10-13 22:21:17]

One minor nit, but LGTM!

[bajones, 2014-10-13 22:22:09]

Grr... silly comment system didn't post my nit

https://codereview.chromium.org/656613002/diff/1/gpu/command_buffer/service/g...
File gpu/command_buffer/service/gles2_cmd_decoder.cc (right):

https://codereview.chromium.org/656613002/diff/1/gpu/command_buffer/service/g...
gpu/command_buffer/service/gles2_cmd_decoder.cc:8618: GL_INVALID_OPERATION,
"glCopyTexImage2D", "feedback loops");
I feel like the error message here and below could be a little more explicit to
help confused developers. Maybe something like "Source and destination texture
are the same"?

[Zhenyao Mo, 2014-10-13 22:31:40]

https://codereview.chromium.org/656613002/diff/1/gpu/command_buffer/service/g...
File gpu/command_buffer/service/gles2_cmd_decoder.cc (right):

https://codereview.chromium.org/656613002/diff/1/gpu/command_buffer/service/g...
gpu/command_buffer/service/gles2_cmd_decoder.cc:8618: GL_INVALID_OPERATION,
"glCopyTexImage2D", "feedback loops");
On 2014/10/13 22:22:09, bajones wrote:
> I feel like the error message here and below could be a little more explicit
to
> help confused developers. Maybe something like "Source and destination texture
> are the same"? 

Done.

[Zhenyao Mo, 2014-10-13 22:31:44]

The CQ bit was checked by zmo@chromium.org

[commit-bot: I haz the power, 2014-10-13 22:33:13]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/656613002/150001

[commit-bot: I haz the power, 2014-10-13 23:30:20]

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

[commit-bot: I haz the power, 2014-10-13 23:30:20]

Try jobs failed on following builders:
  linux_gpu_triggered_tests on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/linux_gpu_trigger...)

[Zhenyao Mo, 2014-10-13 23:34:42]

The CQ bit was checked by zmo@chromium.org

[commit-bot: I haz the power, 2014-10-13 23:36:11]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/656613002/150001

[commit-bot: I haz the power, 2014-10-14 00:11:08]

Committed patchset #2 (id:150001)

[commit-bot: I haz the power, 2014-10-14 00:12:19]

Patchset 2 (id:??) landed as
https://crrev.com/383512cf52d0c163a3fbbd8e9937b5c3c6d80eda
Cr-Commit-Position: refs/heads/master@{#299399}