Allow querying whether an object is capable of holding information that
is relevant to the embedder in its embedder fields.

Bug: chromium:999262
Change-Id: Iced1a1cc78142481990d40d91d8e70e6e5518c5b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1773268Reviewed-by: Adam Klein <adamk@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63463}