This adds data structures to track potentially dead code in the wasm
engine. The engine will then trigger an engine-wide GC once the
potentially dead code reaches a certain threshold.

R=mstarzinger@chromium.org

Bug: v8:8217
Change-Id: I13216a66bb8e8e1594b165a65708e53057e9e535
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1559736
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60718}