[builtins] Migrate Math.clz32 to a TurboFan builtin.

[builtins] Migrate Math.clz32 to a TurboFan builtin.

This allows us to remove the troublesome %_MathClz32 intrinsic and also
allows us to utilize the functionality that is already available in
TurboFan. Also introduce a proper NumberClz32 operator so we don't need
to introduce a machine operator at the JS level.

R=epertoso@chromium.org

Committed: https://crrev.com/eaa92feb9a5a8ab822b478a667482bdf2e9709f7
Cr-Commit-Position: refs/heads/master@{#35208}

[Benedikt Meurer, 2016-04-01 13:00:51]

Hey Enrico,

Another small refactoring.
Please take a look.

Thanks,
Benedikt

[epertoso, 2016-04-01 13:09:34]

lgtm

[Benedikt Meurer (Google), 2016-04-01 14:33:37]

The CQ bit was checked by bmeurer@google.com

[commit-bot: I haz the power, 2016-04-01 14:33:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1852553003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1852553003/1

[commit-bot: I haz the power, 2016-04-01 14:35:35]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-04-01 14:36:41]

Description was changed from

==========
[builtins] Migrate Math.clz32 to a TurboFan builtin.

This allows us to remove the troublesome %_MathClz32 intrinsic and also
allows us to utilize the functionality that is already available in
TurboFan. Also introduce a proper NumberClz32 operator so we don't need
to introduce a machine operator at the JS level.

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

to

==========
[builtins] Migrate Math.clz32 to a TurboFan builtin.

This allows us to remove the troublesome %_MathClz32 intrinsic and also
allows us to utilize the functionality that is already available in
TurboFan. Also introduce a proper NumberClz32 operator so we don't need
to introduce a machine operator at the JS level.

R=epertoso@chromium.org

Committed: https://crrev.com/eaa92feb9a5a8ab822b478a667482bdf2e9709f7
Cr-Commit-Position: refs/heads/master@{#35208}
==========

[commit-bot: I haz the power, 2016-04-01 14:36:43]

Patchset 1 (id:??) landed as
https://crrev.com/eaa92feb9a5a8ab822b478a667482bdf2e9709f7
Cr-Commit-Position: refs/heads/master@{#35208}