v8::TracedReference is supposed to be used from objects allocated on
CppHeap. Such objects can be in construction during garbage
collection, meaning that they are unable to invoke
Trace(v8::TraceReference) as they have not been properly set up.

It is thus necessary to use conservative tracing to find
v8::TracedReference (backed by TracedNode in GlobalHandle) in
in-construction objects.

Change-Id: I5b4ac6e7805ff7ded33f63a405db65ea08d809ad
Bug: v8:13141, chromium:1322114
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3806439
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82188}