Port 1b437aa8

Original Commit Message:

    When we know that the value in a write barrier is a map, we know that
    we are not going to have an old-to-new reference (maps are always in
    old generation). Therefore we also don't really need the generational
    barrier in RecordWrite. While this is technically correct, we don't
    gain much from this optimization. The inline and out-of-line generated
    code for the barrier is still the same as in all other cases. Which
    means that outside marking we don't even reach the RecordWrite builtin.
    Most write barrier executions happen outside incremental marking, hence
    performance of the incremental marking barrier isn't critical. This CL
    always uses the full RecordWrite builtin using a flag in order to
    allow for an easy revert.

    This CL is motivated by the shared heap work, which needs an additional
    always-on barrier in the future (similar to OLD_TO_NEW) to keep a
    OLD_TO_SHARED remembered set up-to-date. While maps are always in the
    old generation, they maybe by located in the shared heap.

R=dinfuehr@chromium.org, joransiu@ca.ibm.com, junyan@redhat.com, midawson@redhat.com
BUG=
LOG=N

Change-Id: I4e763419b3b007a668073e1577cbff9127d15940
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3481263Reviewed-by: Joran Siu <joransiu@ca.ibm.com>
Reviewed-by: Junliang Yan <junyan@redhat.com>
Commit-Queue: Milad Farazmand <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/main@{#79214}