This reverts commit f6e08f43.

This patch doesn't allow thin/cons strings to be inlined as weak refs
to them are not supported by the GC.

Bug: v8:9616
Change-Id: I0407654bd9d20fe0182de4b8554e21ddbce8b28c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1774720
Commit-Queue: Sathya Gunasekaran  <gsathya@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63478}