This reverts commit 77be1c60.

Reason for revert: breaks msan https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Linux%20-%20arm64%20-%20sim%20-%20MSAN/42062/overview

Original change's description:
> factory: Move FeedbackVector construction to type
>
> Drive-by: Avoid unnecessary memset and clean up Init().
>
> Bug: v8:12559
> Change-Id: I6a79f42dd62b47397d70f92efec3b569ca664c3e
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3404097
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#78722}

Bug: v8:12559
Change-Id: I79bea5753eeadf209dc2867c8387cc42c675e567
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3406757
Auto-Submit: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#78724}