Revert of Add unoptimized/optimized variants of MathFloor TF code stub (patchset #4 id:60001 of https://codereview.chromium.org/1225943002/)

Reason for revert:
Failure on compiling runtime.js on windows

Original issue's description:
> Add unoptimized/optimized variants of MathFloor TF code stub
>
> - Add a TurboFanIC class, derived from TurboFanCodeStub, that
>   automatically distinguishes between versions of the IC called from
>   optimized and unoptimized code.
> - Add appropriate InterfaceDescriptors for both the versions of the
>   stub called from unoptimized and optimized code
> - Change the MathFloor TF stub generator to output either the
>   for-optimized or for-unoptimized version based on the minor_key
>   parameter.
>
> Committed: https://crrev.com/8f13b655b8a10dae2116dd18b32f09337bb2d410
> Cr-Commit-Position: refs/heads/master@{#29534}

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

Review URL: https://codereview.chromium.org/1220783006

Cr-Commit-Position: refs/heads/master@{#29535}