gpu: Make CopyTexture work with GL_BGRA_EXT destination textures.

gpu: Make CopyTexture work with GL_BGRA_EXT destination textures.

This allows destination textures with GL_BGRA_EXT as internal format
to be used with CopyTexture.

BUG=371718
Committed: https://crrev.com/6b0fbe4cbbdd357a17c8a72f92535403fa50515a
Cr-Commit-Position: refs/heads/master@{#293245}

[reveman, 2014-09-03 20:27:44]

reveman@chromium.org changed reviewers:
+ dongseong.hwang@intel.com, piman@chromium.org, sievers@chromium.org

[piman, 2014-09-03 20:33:06]

lgtm

[reveman, 2014-09-03 20:34:07]

The CQ bit was checked by reveman@chromium.org

[commit-bot: I haz the power, 2014-09-03 20:35:40]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/reveman@chromium.org/539703002/1

[reveman, 2014-09-03 21:26:57]

The CQ bit was checked by reveman@chromium.org

[commit-bot: I haz the power, 2014-09-03 21:30:21]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/reveman@chromium.org/539703002/20001

[commit-bot: I haz the power, 2014-09-04 00:56:02]

Committed patchset #2 (id:20001) as 3ece8a64100e46cd7cf56fe7e3aef7a55df56746

[commit-bot: I haz the power, 2014-09-10 03:29:19]

Patchset 2 (id:??) landed as
https://crrev.com/6b0fbe4cbbdd357a17c8a72f92535403fa50515a
Cr-Commit-Position: refs/heads/master@{#293245}