Reland of Remove more dead code after Object.observe removal (patchset #1 id:1 of https://codereview.chromium.org/1929293002/ )

This moves __{define,lookup}{Getter,Setter}__ to builtins.cc.

Compared to the first attempt, this patch now preserves non-spec-compliant legacy behavior and does not throw on failure.

Original review: https://codereview.chromium.org/1904313004

Review-Url: https://codereview.chromium.org/1932163002
Cr-Commit-Position: refs/heads/master@{#35899}