[es6] Introduce %ToInteger and %ToLength.

[es6] Introduce %ToInteger and %ToLength.

This adds ES6 compliant Object::ToInteger, Object::ToInt32,
Object::ToUint32 and Object::ToLength, and replaces the old
Execution wrappers of those abstract operations (which were
not using the correct ToPrimitive).

This also introduces proper %ToInteger and %ToLength runtime
entries, with a fast path %_ToInteger supported in fullcodegen
and Crankshaft (for now). Internal JavaScript code should use
TO_INTEGER and TO_LENGTH respectively.

CQ_INCLUDE_TRYBOTS=tryserver.v8:v8_linux_layout_dbg,v8_linux_nosnap_dbg
BUG=v8:4307
LOG=n

Committed: https://crrev.com/93b2b2622ba80d93d036b66736da1346c6e0638c
Cr-Commit-Position: refs/heads/master@{#30993}

[Benedikt Meurer, 2015-09-29 05:27:52]

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

[commit-bot: I haz the power, 2015-09-29 05:28:06]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1378533002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1378533002/1

[Benedikt Meurer, 2015-09-29 06:40:25]

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

[Benedikt Meurer, 2015-09-29 06:40:25]

Hey Camillo,

Here's an easy starter for the day.
Please take a look.

Thanks,
Benedikt

[commit-bot: I haz the power, 2015-09-29 06:43:01]

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

[commit-bot: I haz the power, 2015-09-29 06:43:01]

Dry run: This issue passed the CQ dry run.

[Camillo Bruni, 2015-09-29 07:34:54]

lgtm

[Benedikt Meurer, 2015-09-29 07:39:10]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2015-09-29 07:39:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1378533002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1378533002/1

[commit-bot: I haz the power, 2015-09-29 07:41:11]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-29 07:41:26]

Patchset 1 (id:??) landed as
https://crrev.com/93b2b2622ba80d93d036b66736da1346c6e0638c
Cr-Commit-Position: refs/heads/master@{#30993}