Revert of Also skip when the target is the global object (patchset #1 id:1 of https://codereview.chromium.org/961723002/)

Reason for revert:
Breaks unscopables and fix attempt needed to be reverted too.

Original issue's description:
> Also skip when the target is the global object
>
> BUG=
>
> Committed: https://crrev.com/cc918d30b9d586ce974b71232473f2ae3c5e7847
> Cr-Commit-Position: refs/heads/master@{#26887}

TBR=jkummerow@chromium.org,verwaest@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=

Review URL: https://codereview.chromium.org/960363002

Cr-Commit-Position: refs/heads/master@{#26900}