Fix (most of?) the remaining absl::optional references

There were a lot of references in comments and documentation that
weren't previously picked up. Also a few references in code, which I
assume were a race condition with the bulk of the migration.

Bug: 40242125
Change-Id: Ia9f9332df8c389a55da7bc0b43732a2c1730d664
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5688859
Commit-Queue: David Benjamin <davidben@chromium.org>
Owners-Override: danakj <danakj@chromium.org>
Reviewed-by: danakj <danakj@chromium.org>
Commit-Queue: danakj <danakj@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1325069}
NOKEYCHECK=True
GitOrigin-RevId: 1d737482dacb64165d22433ce79d08b8735d9dbd
1 file changed