[turbofan] Remove threading of FrameStateBeforeAndAfter.

[turbofan] Remove threading of FrameStateBeforeAndAfter.

This removes the by now obsolete threading of the helper class attaching
two frame states (before and after) to a given node. This helper is no
longer required for variable loads and stores.

R=jarin@chromium.org
BUG=v8:5021
Committed: https://crrev.com/2822d2df4003e2e763bea0880db2722f64cefd1a
Cr-Commit-Position: refs/heads/master@{#36829}

[Jarin, 2016-06-08 14:49:31]

lgtm

[Michael Starzinger, 2016-06-08 14:53:17]

The CQ bit was checked by mstarzinger@chromium.org

[commit-bot: I haz the power, 2016-06-08 14:53:27]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2051443003/1

[commit-bot: I haz the power, 2016-06-08 14:55:29]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-06-08 14:55:53]

Description was changed from

==========
[turbofan] Remove threading of FrameStateBeforeAndAfter.

This removes the by now obsolete threading of the helper class attaching
two frame states (before and after) to a given node. This helper is no
longer required for variable loads and stores.

R=jarin@chromium.org
BUG=v8:5021
==========

to

==========
[turbofan] Remove threading of FrameStateBeforeAndAfter.

This removes the by now obsolete threading of the helper class attaching
two frame states (before and after) to a given node. This helper is no
longer required for variable loads and stores.

R=jarin@chromium.org
BUG=v8:5021

Committed: https://crrev.com/2822d2df4003e2e763bea0880db2722f64cefd1a
Cr-Commit-Position: refs/heads/master@{#36829}
==========

[commit-bot: I haz the power, 2016-06-08 14:55:54]

Patchset 1 (id:??) landed as
https://crrev.com/2822d2df4003e2e763bea0880db2722f64cefd1a
Cr-Commit-Position: refs/heads/master@{#36829}