On 32-bit systems the calculation could overflow, leading to an illegal
limit of the LAB. Cast to uint64_t to avoid this. Add DCHECKs to
catch this earlier.

Bug: chromium:1110214, v8:10315
Change-Id: I73679a2daeb3b83bb303d411c77782a2172e98cc
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2320654Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69101}