We previously enumberated properties and then restricted them
to real named properties. This CL changes it to only enumerate
own properties in the first place.

Bug: chromium:1213393
Change-Id: I8665a19a9beccae3bef99106924b65fb219d48ca
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2953284Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75094}