Revert of VectorICs: megamorphic keyed loads in crankshaft don't need a vector.

Revert of VectorICs: megamorphic keyed loads in crankshaft don't need a vector. (patchset #3 id:40001 of https://codereview.chromium.org/1067573003/)

Reason for revert:
[Sheriff] Speculative revert for windows failure... will reland if it doesn't help:
http://build.chromium.org/p/client.v8/builders/V8%20Win32%20-%20debug%20-%202/builds/2891

Original issue's description:
> VectorICs: megamorphic keyed loads in crankshaft don't need a vector.
>
> They are content with a dummy vector, as MISSES won't result in
> changing the real vector/slot at all.
>
> BUG=
>
> Committed: https://crrev.com/c8e4d57d3b3036a05902f5b916cb5d853a57393c
> Cr-Commit-Position: refs/heads/master@{#27788}

TBR=dcarney@chromium.org,mvstanton@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=

Committed: https://crrev.com/dc65e62abde16c36c9f5ebb878c92674e651a58e
Cr-Commit-Position: refs/heads/master@{#27790}

[Michael Achenbach, 2015-04-13 16:18:58]

Created Revert of VectorICs: megamorphic keyed loads in crankshaft don't need a
vector.

[commit-bot: I haz the power, 2015-04-13 16:19:15]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1060263003/1

[commit-bot: I haz the power, 2015-04-13 16:19:35]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-04-13 16:19:48]

Patchset 1 (id:??) landed as
https://crrev.com/dc65e62abde16c36c9f5ebb878c92674e651a58e
Cr-Commit-Position: refs/heads/master@{#27790}