Reland "[es6] Better support for built-ins subclassing."

Reland "[es6] Better support for built-ins subclassing."

Original issue's description:
> [es6] Better support for built-ins subclassing.
>
> Create proper initial map for original constructor (new.target) instead of doing prototype
> transition on the base constructor's initial map. This approach fixes in-object slack tracking
> for subclass instances.
> This CL also fixes subclassing from String.
>
> BUG=v8:3101, v8:3330
> LOG=Y
>
> Committed: https://crrev.com/cd5f48302a502154a0106d12e3066bd563c6340c
> Cr-Commit-Position: refs/heads/master@{#31680}

It also fixes typed array map smashing done during typed array initialization.

BUG=v8:3101, v8:3330, v8:4419
LOG=Y

Committed: https://crrev.com/4490ce85205d3504dc0bf444f5e8b3deb04cbb06
Cr-Commit-Position: refs/heads/master@{#31701}

[Igor Sheludko, 2015-10-30 14:13:25]

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

[Igor Sheludko, 2015-10-30 14:13:40]

ishell@chromium.org changed reviewers:
+ bmeurer@chromium.org

[Igor Sheludko, 2015-10-30 14:13:40]

PTAL

[commit-bot: I haz the power, 2015-10-30 14:14:15]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1413033006/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1413033006/20001

[Benedikt Meurer, 2015-10-30 14:14:58]

LGTM (rubber-stamped)

[Igor Sheludko, 2015-10-30 16:00:44]

Patchset #2 (id:20001) has been deleted

[Igor Sheludko, 2015-10-30 16:00:50]

Patchset #2 (id:40001) has been deleted

[Igor Sheludko, 2015-10-30 16:01:12]

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

[commit-bot: I haz the power, 2015-10-30 16:01:16]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1413033006/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1413033006/60001

[commit-bot: I haz the power, 2015-10-30 16:34:21]

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

[commit-bot: I haz the power, 2015-10-30 16:34:22]

Dry run: Try jobs failed on following builders:
  v8_linux_arm64_rel on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_linux_arm64_rel/builds/1...)

[Igor Sheludko, 2015-10-30 17:21:17]

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

[commit-bot: I haz the power, 2015-10-30 17:21:23]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1413033006/80001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1413033006/80001

[commit-bot: I haz the power, 2015-10-30 17:55:13]

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

[commit-bot: I haz the power, 2015-10-30 17:55:14]

Dry run: This issue passed the CQ dry run.

[Igor Sheludko, 2015-11-02 07:53:35]

Description was changed from

==========
Reland "[es6] Better support for built-ins subclassing."

Original issue's description:
> [es6] Better support for built-ins subclassing.
>
> Create proper initial map for original constructor (new.target) instead of
doing prototype
> transition on the base constructor's initial map. This approach fixes
in-object slack tracking
> for subclass instances.
> This CL also fixes subclassing from String.
>
> BUG=v8:3101, v8:3330
> LOG=Y
>
> Committed: https://crrev.com/cd5f48302a502154a0106d12e3066bd563c6340c
> Cr-Commit-Position: refs/heads/master@{#31680}

BUG=v8:3101, v8:3330
LOG=Y
==========

to

==========
Reland "[es6] Better support for built-ins subclassing."

Original issue's description:
> [es6] Better support for built-ins subclassing.
>
> Create proper initial map for original constructor (new.target) instead of
doing prototype
> transition on the base constructor's initial map. This approach fixes
in-object slack tracking
> for subclass instances.
> This CL also fixes subclassing from String.
>
> BUG=v8:3101, v8:3330
> LOG=Y
>
> Committed: https://crrev.com/cd5f48302a502154a0106d12e3066bd563c6340c
> Cr-Commit-Position: refs/heads/master@{#31680}

BUG=v8:3101, v8:3330, v8:4419
LOG=Y
==========

[Igor Sheludko, 2015-11-02 07:58:19]

Description was changed from

==========
Reland "[es6] Better support for built-ins subclassing."

Original issue's description:
> [es6] Better support for built-ins subclassing.
>
> Create proper initial map for original constructor (new.target) instead of
doing prototype
> transition on the base constructor's initial map. This approach fixes
in-object slack tracking
> for subclass instances.
> This CL also fixes subclassing from String.
>
> BUG=v8:3101, v8:3330
> LOG=Y
>
> Committed: https://crrev.com/cd5f48302a502154a0106d12e3066bd563c6340c
> Cr-Commit-Position: refs/heads/master@{#31680}

BUG=v8:3101, v8:3330, v8:4419
LOG=Y
==========

to

==========
Reland "[es6] Better support for built-ins subclassing."

Original issue's description:
> [es6] Better support for built-ins subclassing.
>
> Create proper initial map for original constructor (new.target) instead of
doing prototype
> transition on the base constructor's initial map. This approach fixes
in-object slack tracking
> for subclass instances.
> This CL also fixes subclassing from String.
>
> BUG=v8:3101, v8:3330
> LOG=Y
>
> Committed: https://crrev.com/cd5f48302a502154a0106d12e3066bd563c6340c
> Cr-Commit-Position: refs/heads/master@{#31680}

It also fixes typed array map smashing done during typed array initialization.

BUG=v8:3101, v8:3330, v8:4419
LOG=Y
==========

[Igor Sheludko, 2015-11-02 07:58:34]

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

[commit-bot: I haz the power, 2015-11-02 07:58:47]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1413033006/100001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1413033006/100001

[Igor Sheludko, 2015-11-02 07:59:46]

Patchset #2 (id:60001) has been deleted

[Igor Sheludko, 2015-11-02 07:59:56]

Patchset #2 (id:80001) has been deleted

[Igor Sheludko, 2015-11-02 08:07:57]

ishell@chromium.org changed reviewers:
+ verwaest@chromium.org

[Igor Sheludko, 2015-11-02 08:07:58]

PTAL

I removed harmful typed array map smashing because 1) the object we create
already has the right map, 2) we used to do that only (!) in crankshaft
implementation of the %_TypedArrayInitialize

[Benedikt Meurer, 2015-11-02 08:12:11]

Nice, thanks. LGTM

[Igor Sheludko, 2015-11-02 08:13:32]

The CQ bit was unchecked by ishell@chromium.org

[Igor Sheludko, 2015-11-02 08:13:38]

The CQ bit was checked by ishell@chromium.org

[commit-bot: I haz the power, 2015-11-02 08:13:45]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1413033006/100001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1413033006/100001

[commit-bot: I haz the power, 2015-11-02 08:16:05]

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

[commit-bot: I haz the power, 2015-11-02 08:16:06]

Try jobs failed on following builders:
  v8_presubmit on tryserver.v8 (JOB_FAILED,
http://build.chromium.org/p/tryserver.v8/builders/v8_presubmit/builds/7275)

[ulan, 2015-11-02 08:22:51]

ulan@chromium.org changed reviewers:
+ ulan@chromium.org

[ulan, 2015-11-02 08:22:51]

lgtm

[ulan, 2015-11-02 08:23:36]

The CQ bit was checked by ulan@chromium.org

[commit-bot: I haz the power, 2015-11-02 08:23:45]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1413033006/100001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1413033006/100001

[commit-bot: I haz the power, 2015-11-02 08:25:26]

Committed patchset #2 (id:100001)

[commit-bot: I haz the power, 2015-11-02 08:26:02]

Patchset 2 (id:??) landed as
https://crrev.com/4490ce85205d3504dc0bf444f5e8b3deb04cbb06
Cr-Commit-Position: refs/heads/master@{#31701}