exo: Avoid creating transparent texture quads.

exo: Avoid creating transparent texture quads.

The surface is fully transparent when alpha is 0 and we can then
avoid to create a texture quad completely. Failing to do so
currently results in unnecessary compositing.

BUG=640805
TEST=exo_unittests

Committed: https://crrev.com/e2d54b85fbc32bd0d19e1741677a296e25fd47c7
Cr-Commit-Position: refs/heads/master@{#414220}

[reveman, 2016-08-24 23:34:13]

reveman@chromium.org changed reviewers:
+ dcastagna@chromium.org, jbauman@chromium.org

[reveman, 2016-08-24 23:34:19]

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

[commit-bot: I haz the power, 2016-08-24 23:35:35]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[jbauman, 2016-08-24 23:37:01]

lgtm

[reveman, 2016-08-24 23:39:30]

The CQ bit was unchecked by reveman@chromium.org

[reveman, 2016-08-24 23:39:32]

The CQ bit was checked by reveman@chromium.org

[commit-bot: I haz the power, 2016-08-24 23:40:23]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-25 00:30:54]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-08-25 00:33:47]

Description was changed from

==========
exo: Avoid creating transparent texture quads.

The surface is fully transparent when alpha is 0 and we can then
avoid to create a texture quad completely. Failing to do so
currently results in unnecessary compositing.

BUG=640805
TEST=exo_unittests
==========

to

==========
exo: Avoid creating transparent texture quads.

The surface is fully transparent when alpha is 0 and we can then
avoid to create a texture quad completely. Failing to do so
currently results in unnecessary compositing.

BUG=640805
TEST=exo_unittests

Committed: https://crrev.com/e2d54b85fbc32bd0d19e1741677a296e25fd47c7
Cr-Commit-Position: refs/heads/master@{#414220}
==========

[commit-bot: I haz the power, 2016-08-25 00:33:48]

Patchset 1 (id:??) landed as
https://crrev.com/e2d54b85fbc32bd0d19e1741677a296e25fd47c7
Cr-Commit-Position: refs/heads/master@{#414220}