Mac: Reset active texture state when drawing CAOpenGLLayer

Mac: Reset active texture state when drawing CAOpenGLLayer

When GPU raster is enabled, the active texture state is regularly set to
something different at the start of this function. This was observed
empirically.

Of note is that, in principle, all GL state much be reset. When we use
the command buffer to draw inside the CAOpenGLLayer, making the virtual
context current will reset all state for us.

BUG=423163
Committed: https://crrev.com/d65ea042b964ae0833ecd6ed4f19852c4d334ca6
Cr-Commit-Position: refs/heads/master@{#321613}

[ccameron, 2015-03-19 23:57:12]

ccameron@chromium.org changed reviewers:
+ vmiura@chromium.org

[ccameron, 2015-03-19 23:57:12]

1-line almost-fix. I'm hoping to get the context merge bit in soon (which will
make the whole blit unneeded).

[vmiura, 2015-03-20 02:13:31]

lgtm

[ccameron, 2015-03-20 18:37:07]

Thanks!

[ccameron, 2015-03-20 18:37:14]

The CQ bit was checked by ccameron@chromium.org

[commit-bot: I haz the power, 2015-03-20 18:37:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1023673006/1

[commit-bot: I haz the power, 2015-03-20 19:16:00]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-03-20 19:16:45]

Patchset 1 (id:??) landed as
https://crrev.com/d65ea042b964ae0833ecd6ed4f19852c4d334ca6
Cr-Commit-Position: refs/heads/master@{#321613}