spanification: automatically spanify various pointers

This is the result of running the automatic spanification on linux and
updating code to use and pass spans where size is known. This CL has no
behavior changes.

All changes should be correct and no behaviour changes in patchset 1,
however the plan is to follow up and remove the redundant size
parameters. To this effect in patchset 2 we've added CHECKS and renames
to note the fact the size is believed to be redundant. This was done
through AI and should be carefully checked, but the CHECKS are not fatal
and thus if unsure should be fine to land and remove after reports of
the crashes.

The original patch was fully automated using script:
//tools/clang/spanify/rewrite-multiple-platforms.sh -platforms=linux

and then split with `git cl split --target-range 8 32 --max-depth=2
--no-reviewers -d ~/description.txt`

This covers directories: base

This is part of auto spanification see internal doc about it:
https://docs.google.com/document/u/1/d/1poEhNARfFas2osqPoXGzVZtBgnOQGQtQNUFTA-MlADs/edit?tab=t.0

This CL was uploaded by an experimental version of git cl split
(https://crbug.com/389069356).

Bug: 431824299
Change-Id: Ic568526fa0de3d8f1c388d1b7f9460a1ad2599fa
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6731986
Auto-Submit: Stephen Nusko <nuskos@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1492961}