Revert of [turbofan] Make Factory::NewNumber() always return the minus_zero_value. (patchset #1 id:1 of https://codereview.chromium.org/838263006/)

Reason for revert:
Breaks the tree

Original issue's description:
> [turbofan] Make Factory::NewNumber() always return the minus_zero_value.
>
> TEST=unittests
> R=mstarzinger@chromium.org, dcarney@chromium.org
>
> Committed: https://crrev.com/55b3e268b2895e2c09230d39669a75b6ab4e7e4d
> Cr-Commit-Position: refs/heads/master@{#26080}

TBR=dcarney@chromium.org,mstarzinger@chromium.org
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/853683009

Cr-Commit-Position: refs/heads/master@{#26081}