Also access the DescriptorArray through GetFieldType concurrently if
the FLAG_turbo_direct_heap_access is on.

Bug: v8:7790
Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_isolates_rel_ng
Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_no_cm_rel_ng
Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_rel_ng
Change-Id: I2506fe44a3be9f3474934300d52849f278899e70
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2720299Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73149}