Revert "Unify modeling logic for holding space sections."

This reverts commit 89bf6045d56e8b33cc41d4b788d16c901a55e7b9.

Reason for revert: Causing build failure in Linux ChromiumOS Full 

Original change's description:
> Unify modeling logic for holding space sections.
>
> Currently holding space sections have a concept of:
> * supported holding space item types
> * max item counts
> * max visible item counts
>
> These parameters are inconsistently spread across the code base. This
> CL unifies all holding space section parameters in:
>
> //ash/public/cpp/holding_space/holding_space_sections
>
> Special casing for screen captures and downloads sections in the model
> has also been removed.
>
> Bug: 1363825
> Change-Id: Ic1d828a365fdf694cd36545757938ec1e1ae1234
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3897454
> Reviewed-by: Toni Barzic <tbarzic@chromium.org>
> Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
> Commit-Queue: David Black <dmblack@google.com>
> Cr-Commit-Position: refs/heads/main@{#1049704}

Bug: 1363825
Change-Id: I04479d57b7f70429dbea6e50d37e38c158895c9a
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3909420
Commit-Queue: Alex Moshchuk <alexmos@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Owners-Override: Alex Moshchuk <alexmos@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1049714}