This field is no longer used, as the functionality it supported has been
subsumed by wasm-gc typed-based optimizations.

Bug: v8:7748
Change-Id: I970514bb29e5f91bb5610cafde60ec3dbcfb07aa
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3705376
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81244}