Advance deprecations and remove fully deprecated code.

Bug: v8:12165
Change-Id: I2cf1715d6878ff65e5b9beaddb8df7aec780b21e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3328781
Auto-Submit: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Commit-Queue: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78329}

... and thus avoid the need for special handling of objects located
in external code space.

This will also allow making HeapObject::IsBlah() checks faster when
external code space is enabled.

Bug: v8:11880
Change-Id: I12d07c05451ff198f0a6182d9b5849f76015e7fb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3300140Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78104}

Explicit write barriers for internal fields are deprecated as they are
automatically emitted by V8.

Depends on:
  https://crrev.com/c/3263924

Bug: v8:12356
Change-Id: I171ba5b42a6570ce52e2e2ea1b7c1029d5a8a3a7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3263888Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77772}

Internal fields are used for implementing edges to C++ objects in
Oilpan. When setting the fields on a JS API object, we should also
emit a write barrier for this edge.

This mechanism replaces the explicit write barrier in V8's API which
is provided through `JSHeapConsistency::*`.

The internal barrier should also be slightly faster as it doesn't
require any API calls.

Bug: v8:12356
Change-Id: I639d18141acfb910d0ded8d987d8a0916e25431d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3257709
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77749}

Adjust WATCHLISTS to only send out updates to those testfiles as part
of notifying oilpan-reviews+v8@.

Change-Id: Ib877f0353ea2b2d1ac06c93d450145dbeb6fcc66
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3260517
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Auto-Submit: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77713}