This has been made possible when custom builtin constructors were
removed.

R=jgruber@chromium.org

Bug: v8:178, v8:7518
Change-Id: I7ee064c3b899732ebe9381ea004f231fa6c0cef0
Reviewed-on: https://chromium-review.googlesource.com/975541
Commit-Queue: Yang Guo <yangguo@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52229}