Prefer using the wasm engine's allocator, as the isolate may not be
available during asynchronous compilation.

Bug: v8:9554
Change-Id: Iee3777efb62d18de6b2a64fa7a71d4ef4c6b3a92
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1722559
Commit-Queue: Thibaud Michaud <thibaudm@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62955}