This should avoid changes in code serializer in a follow-up class literals
improvement CL.

Bug: v8:5799
Change-Id: I4e4386333bcc7abb30399d4e9abba4eee80ca932
Reviewed-on: https://chromium-review.googlesource.com/733037
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48996}