Remove base/memory/raw_ptr.h dependency

Google3 already just patches these out this way today

Bug: 1322914
Change-Id: I551a1c37a38a3843ac7d659cd1b11fa8e95cf97c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4054293


Commit-Queue: Bob Beck <bbe@google.com>
Reviewed-by: David Benjamin <davidben@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1076497}