This reverts commit f05bae1e.

Reason for revert: broke arm sim debug
https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20arm64%20-%20sim%20-%20debug/17714

https://logs.chromium.org/logs/v8/buildbucket/cr-buildbucket.appspot.com/8899519852984476944/+/steps/Check_-_trusted/0/logs/FunctionDetailsInlining/0

Original change's description:
> [runtime] Move Context::native_context to the map
> 
> Remove the native context slot from contexts by making context maps
> native-context-specific. Now we require 2 loads to go from a context to the
> native context, but we have 1 field fewer to store when creating contexts.
> 
> Change-Id: I3c0d7c50c94060c4129db684f46a567de6f30e8d
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1859629
> Commit-Queue: Toon Verwaest <verwaest@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Peter Marshall <petermarshall@chromium.org>
> Reviewed-by: Maya Lekova <mslekova@chromium.org>
> Reviewed-by: Georg Neis <neis@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#64296}

TBR=ulan@chromium.org,neis@chromium.org,petermarshall@chromium.org,ishell@chromium.org,verwaest@chromium.org,mslekova@chromium.org,victorgomes@google.com

Change-Id: Ie7b4086c3a9ab2627ecac599da36b20cf8d1f948
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1863200Reviewed-by: Sathya Gunasekaran  <gsathya@chromium.org>
Commit-Queue: Sathya Gunasekaran  <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64299}