Revert of [heap] Prepare code for smaller large object allocation limit than max allocatable memory. (patchset #10 id:180001 of https://codereview.chromium.org/1361853005/ )

Reason for revert:
[Sheriff] Need to revert for reverting https://codereview.chromium.org/1358703003/

Original issue's description:
> [heap] Prepare heap for smaller large object allocation limit than max allocatable memory.
>
> BUG=chromium:524425
> LOG=n
>
> Committed: https://crrev.com/c2bce747993c445daf78975392e587bff20c6677
> Cr-Commit-Position: refs/heads/master@{#31107}

TBR=mlippautz@chromium.org,mstarzinger@chromium.org,hpayer@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:524425

Review URL: https://codereview.chromium.org/1376413005

Cr-Commit-Position: refs/heads/master@{#31129}