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

Bug: v8:7503
Change-Id: I9502246f5e463e487a989ab7f8c96c008f0fa9d9
Reviewed-on: https://chromium-review.googlesource.com/941143
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51634}