Temporarily behind a new flag: --new-wasm-dynamic-tiering
The plan is to merge this into the existing --wasm-dynamic-tiering
flag once it's been confirmed to be generally beneficial.

Bug: v8:12281
Change-Id: I191d03170f8d5360073a45fea170f432074f7534
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3247632Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77620}