.. which used to be implemented by calling BooleanValue eagerly on all
seen heap objects during serialization. 1) it's wasteful to call this
on every object, 2) this was blocking conversion of HeapObjectRefs to
not require main-thread serialization.

This CL replaces the old pattern by a thread-safe TryGetBooleanValue
method, which may fail in some cases (e.g. when trying to read into a
HeapNumber).

Bug: v8:7790
Change-Id: I9d4ab7725231adce0b488c4c08c1f4bac78ce3c5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2839557
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Auto-Submit: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74165}