[turbofan] Add support for String.prototype.charCodeAt/charAt.

[turbofan] Add support for String.prototype.charCodeAt/charAt.

Introduce an appropriate StringCharCodeAt simplified operator and use
that to optimize the String.prototype.charCodeAt/.charAt builtins.

R=epertoso@chromium.org

Committed: https://crrev.com/5340f767584749d604a9ce1abc9b14547fcf0e35
Cr-Commit-Position: refs/heads/master@{#38106}

[Benedikt Meurer, 2016-07-27 13:02:00]

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

[commit-bot: I haz the power, 2016-07-27 13:02:02]

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, 2016-07-27 13:24:52]

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

[commit-bot: I haz the power, 2016-07-27 13:24:53]

Dry run: This issue passed the CQ dry run.

[epertoso, 2016-07-27 14:53:17]

lgtm

[Benedikt Meurer, 2016-07-27 17:24:47]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2016-07-27 17:24:50]

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, 2016-07-27 17:26:30]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-07-27 17:29:59]

Description was changed from

==========
[turbofan] Add support for String.prototype.charCodeAt/charAt.

Introduce an appropriate StringCharCodeAt simplified operator and use
that to optimize the String.prototype.charCodeAt/.charAt builtins.

R=epertoso@chromium.org
==========

to

==========
[turbofan] Add support for String.prototype.charCodeAt/charAt.

Introduce an appropriate StringCharCodeAt simplified operator and use
that to optimize the String.prototype.charCodeAt/.charAt builtins.

R=epertoso@chromium.org

Committed: https://crrev.com/5340f767584749d604a9ce1abc9b14547fcf0e35
Cr-Commit-Position: refs/heads/master@{#38106}
==========

[commit-bot: I haz the power, 2016-07-27 17:30:00]

Patchset 1 (id:??) landed as
https://crrev.com/5340f767584749d604a9ce1abc9b14547fcf0e35
Cr-Commit-Position: refs/heads/master@{#38106}