Update {virtual,override,final} to follow C++11 style in chrome, round 2.

Update {virtual,override,final} to follow C++11 style in chrome, round 2.

The Google style guide states that only one of {virtual,override,final}
should be used for each declaration, since override implies virtual and
final implies both virtual and override.

This patch was automatically generated with a ChromeOS build using a
variation of https://codereview.chromium.org/598073004.

BUG=417463
Committed: https://crrev.com/8dafeb843c148804b63d5728fe3153d7b1b53a12
Cr-Commit-Position: refs/heads/master@{#312740}

[dcheng, 2015-01-22 22:28:23]

dcheng@chromium.org changed reviewers:
+ thestig@chromium.org

[Lei Zhang, 2015-01-22 22:50:17]

lgtm

[dcheng, 2015-01-22 22:57:05]

The CQ bit was checked by dcheng@chromium.org

[commit-bot: I haz the power, 2015-01-22 22:58:59]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/869753002/20001

[commit-bot: I haz the power, 2015-01-23 01:04:16]

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

[commit-bot: I haz the power, 2015-01-23 01:04:17]

Exceeded time limit waiting for builds to trigger.

[dcheng, 2015-01-23 01:05:33]

The CQ bit was checked by dcheng@chromium.org

[commit-bot: I haz the power, 2015-01-23 01:06:48]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/869753002/20001

[commit-bot: I haz the power, 2015-01-23 01:51:25]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-01-23 01:52:31]

Patchset 2 (id:??) landed as
https://crrev.com/8dafeb843c148804b63d5728fe3153d7b1b53a12
Cr-Commit-Position: refs/heads/master@{#312740}