Revert of Pool implementation for zone segments (patchset #13 id:520001 of https://codereview.chromium.org/2335343007/ )

Reason for revert:
blocks roll: https://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_x64_rel_ng/builds/294283/steps/compile%20%28with%20patch%29/logs/stdio

Original issue's description:
> Pool implementation for zone segments
>
> BUG=v8:5409
>
> Committed: https://crrev.com/37c688a24578e787d3d8941093563ed049c3497e
> Committed: https://crrev.com/316669f62ea3834395bf4caab7bc3d7c32f6bbc6
> Cr-Original-Commit-Position: refs/heads/master@{#39631}
> Cr-Commit-Position: refs/heads/master@{#40044}

TBR=jochen@chromium.org,jkummerow@chromium.org,verwaest@chromium.org,yangguo@chromium.org,heimbuef@google.com
NOTRY=true
NOPRESUBMIT=true
NOTREECHECKS=true
BUG=v8:5409

Review-Url: https://codereview.chromium.org/2400343002
Cr-Commit-Position: refs/heads/master@{#40100}