[turbofan] Revive the VectorSlotPair and also put feedback on JSCallFunction.

[turbofan] Revive the VectorSlotPair and also put feedback on JSCallFunction.

We resurrect the VectorSlotPair in order to be able to separate the
feedback input for the compiler from the actual type feedback vector
that is required to meet the IC requirements at runtime. This will allow
us to for example use feedback from a different context or divide the
type feedback vector into two separate vectors, without having to touch
the compiler. It'll allow use to load the vector from the shared
function info at runtime, while still consuming feedback in the
compiler (i.e. we don't rely on the feedback vector node to be a heap
constant).

R=mvstanton@chromium.org

Committed: https://crrev.com/d4f70f8ce8f523f6ea5986b59923c133747338c6
Cr-Commit-Position: refs/heads/master@{#29185}

[Benedikt Meurer, 2015-06-22 11:07:08]

Hey Michael,

This is the change we were talking about. Mostly straight forward.
Please take a look.

Thanks,
Benedikt

[mvstanton, 2015-06-22 11:24:08]

Okay, LGTM...

[Benedikt Meurer, 2015-06-22 12:03:03]

The CQ bit was checked by bmeurer@chromium.org

[commit-bot: I haz the power, 2015-06-22 12:03:08]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1198983002/20001

[commit-bot: I haz the power, 2015-06-22 12:08:10]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-06-22 12:08:29]

Patchset 2 (id:??) landed as
https://crrev.com/d4f70f8ce8f523f6ea5986b59923c133747338c6
Cr-Commit-Position: refs/heads/master@{#29185}