Automatically annotate dangling ExperimentalAsh pointers [11/N]

This patch is:
- Automated. See [automation] section.
- Not affecting users, only Chrome's CQ. See [no-op] section.

This split is about the new dangling pointer that got added the last few
days.

Context:
--------
@bartekn is going to remove the `ExperimentalAsh` raw_ptr annotation.
This was a performance experiment to enable/disable MiraclePtr on a
subset of new pointers added for ChromeOS ash (non-lacros).

Before removing it, he needs to enable it by default in code. Enabling
MiraclePtr for them, causes the DanglingPointerDetector to be enforced.
To pass the CQ, we need to annotate pre-existing dangling pointer with
`DanglingUntriaged`. After enabling ExperimentalAsh feature, it won't be
allowed anymore for those pointers to become dangling.

Automation:
-----------
1. Enable the `PartitionAllocBackupRefPtrForAsh` feature flag.
2. Apply the 'annotator' CL: https://chromium-review.googlesource.com/c/chromium/src/+/4474553
3. Run all the gtests. See https://docs.google.com/document/d/1AMMERcqy0eafFWopUCHYsIKIKEp3J8DFxqW9UIbzIHo
4. Concatenate all the output_*, `filter`, `sort -nr`, `uniq`.
5. Run https://github.com/ArthurSonzogni/chrome-dangling-ptr-apply-edit
6. Run `git cl format`
7. Cherry-pick the patch created from (5)

no-op:
------
The DanglingPointerDetector is not enabled against users. It only
affects tests and chromium developers.

AX-Relnotes: n/a.
Bug: chromium:1441101
Change-Id: I4bd8504c4545477d09c44aaed750ae3c7acfe5ed
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4793514
Commit-Queue: Arthur Sonzogni <arthursonzogni@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Daniel Cheng <dcheng@chromium.org>
Auto-Submit: Arthur Sonzogni <arthursonzogni@chromium.org>
Owners-Override: Daniel Cheng <dcheng@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1186809}