Remove |cgl_context| from VTVideoDecodeAccelerator.

Remove |cgl_context| from VTVideoDecodeAccelerator.

Instead of explicitly passing |cgl_context|, get it from
GLContext::GetCurrent().

Committed: https://crrev.com/ea47d8141292d0b6f87fe292a795c655460afaab
Cr-Commit-Position: refs/heads/master@{#338219}

[sandersd (OOO until July 31), 2015-07-10 00:50:41]

sandersd@chromium.org changed reviewers:
+ dalecurtis@chromium.org

[sandersd (OOO until July 31), 2015-07-10 00:50:42]

Not very different, but |cgl_context| was only used for
CGLTexImageIOSurface2D(). GLImageIOSurface, the proposed replacement for
CGLTexImageIOSurface2D() in this code, uses this pattern internally, so the
parameter will become useless if we switch.

[DaleCurtis, 2015-07-10 00:53:46]

lgtm % question

https://codereview.chromium.org/1228253002/diff/1/content/common/gpu/media/vt...
File content/common/gpu/media/vt_video_decode_accelerator.cc (right):

https://codereview.chromium.org/1228253002/diff/1/content/common/gpu/media/vt...
content/common/gpu/media/vt_video_decode_accelerator.cc:1011:
glDisable(GL_TEXTURE_RECTANGLE_ARB);
Why the move to before the status is checked?

[sandersd (OOO until July 31), 2015-07-10 00:59:16]

On 2015/07/10 00:53:46, DaleCurtis wrote:
> lgtm % question
> 
>
https://codereview.chromium.org/1228253002/diff/1/content/common/gpu/media/vt...
> File content/common/gpu/media/vt_video_decode_accelerator.cc (right):
> 
>
https://codereview.chromium.org/1228253002/diff/1/content/common/gpu/media/vt...
> content/common/gpu/media/vt_video_decode_accelerator.cc:1011:
> glDisable(GL_TEXTURE_RECTANGLE_ARB);
> Why the move to before the status is checked?

Just to make sure the correct OpenGL state is restored before any possible
return path.

[DaleCurtis, 2015-07-10 01:00:07]

Ah didn't see the glEnable above. lgtm!

[sandersd (OOO until July 31), 2015-07-10 01:01:15]

The CQ bit was checked by sandersd@chromium.org

[commit-bot: I haz the power, 2015-07-10 01:03:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1228253002/1

[commit-bot: I haz the power, 2015-07-10 02:41:41]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-07-10 02:43:09]

Patchset 1 (id:??) landed as
https://crrev.com/ea47d8141292d0b6f87fe292a795c655460afaab
Cr-Commit-Position: refs/heads/master@{#338219}