This reverts commit b0c4a876.

Reason for revert:
https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20arm64%20-%20sim%20-%20MSAN/26470

Original change's description:
> [json] Speed up json parsing
> 
> - scan using raw data pointers + GC callback
> - scan using scanner tables
> - cap internalizing large string values
> - inline fast transitioning logic
> 
> Fixes previous CL by moving AllowHeapAllocation to callers of
> ReportUnexpectedCharacter where needed to make it clear we need to exit.
> 
> Tbr: ulan@chromium.org
> Change-Id: Icfbb7cd536e0fbe153f34acca5d0fab6b5453d71
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1591778
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Commit-Queue: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#61159}

TBR=ulan@chromium.org,ishell@google.com,ishell@chromium.org,verwaest@chromium.org

Change-Id: Ibe823e187d9ab999be7278140b0ed31868440e9e
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1593090Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61163}