arc: Add the --arc-available switch

arc: Add the --arc-available switch

A previous change added a Chrome Variation to allow enabling ARC.
This change adds another flag to ensure that the board Chrome is running
on actually has the bits to enable it and avoid showing people the UI
when it is not actually supported.

BUG=633704
TEST=ARC still works

Committed: https://crrev.com/49634287993d6b2efd137ddce7d4196e7ebc6fd1
Cr-Commit-Position: refs/heads/master@{#413908}

[Luis Héctor Chávez, 2016-08-22 19:26:09]

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

[commit-bot: I haz the power, 2016-08-22 19:27:11]

Dry run: 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, 2016-08-22 21:14:49]

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

[commit-bot: I haz the power, 2016-08-22 21:14:50]

Dry run: This issue passed the CQ dry run.

[Luis Héctor Chávez, 2016-08-22 22:33:49]

lhchavez@chromium.org changed reviewers:
+ achuith@chromium.org, yusukes@chromium.org

[Luis Héctor Chávez, 2016-08-22 22:33:49]

PTAL

achuith: chrome/browser/chromeos/, chromeos/
yusukes: components/arc

[achuithb, 2016-08-22 22:46:31]

lgtm

[Yusuke Sato, 2016-08-22 22:54:59]

lgtm

[Luis Héctor Chávez, 2016-08-23 23:17:02]

The CQ bit was checked by lhchavez@chromium.org

[commit-bot: I haz the power, 2016-08-23 23:17:54]

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, 2016-08-24 00:36:36]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-08-24 00:38:36]

Description was changed from

==========
arc: Add the --arc-available switch

A previous change added a Chrome Variation to allow enabling ARC.
This change adds another flag to ensure that the board Chrome is running
on actually has the bits to enable it and avoid showing people the UI
when it is not actually supported.

BUG=633704
TEST=ARC still works
==========

to

==========
arc: Add the --arc-available switch

A previous change added a Chrome Variation to allow enabling ARC.
This change adds another flag to ensure that the board Chrome is running
on actually has the bits to enable it and avoid showing people the UI
when it is not actually supported.

BUG=633704
TEST=ARC still works

Committed: https://crrev.com/49634287993d6b2efd137ddce7d4196e7ebc6fd1
Cr-Commit-Position: refs/heads/master@{#413908}
==========

[commit-bot: I haz the power, 2016-08-24 00:38:37]

Patchset 1 (id:??) landed as
https://crrev.com/49634287993d6b2efd137ddce7d4196e7ebc6fd1
Cr-Commit-Position: refs/heads/master@{#413908}