TypedSlotSet is only recorded for code pages. Code pages are not swept
concurrently to the application, so pre-freeing is not needed for typed
slot sets anymore.

Also replaces the manually allocated buffer with a regular std::vector.

Bug: v8:9454
Change-Id: I901851ad8b525c1653c9818e6599308319aeade2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1844773Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64140}