It was recently changed to Tagged in
https://chromium-review.googlesource.com/c/v8/v8/+/1832174,
but IntPtr is a better choice since we are doing an IntPtr
equality check below.

AnyTagged loads will decompress in the near future. Then,
https://chromium-review.googlesource.com/c/v8/v8/+/1822637 needs
this CL before submission since otherwise we will be decompressing a
value that we don't need to decompress.

Change-Id: Ifb44faaf84fd68e168c5f99b72c316aa1e5b9f13
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1847360
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64177}