This brings us closer to our goal of deprecating the `construct_stub`
field in `SharedFunctionInfo`.

Bug: v8:7503
Change-Id: I0e995e6ed9e7c04990f76dd8fe8afaaa8d38294b
Reviewed-on: https://chromium-review.googlesource.com/940124
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51629}