[Android][SA] Add subpage to SA site settings

This CL groups storage access site exceptions by requesting origin. It
adds a different site exception row that leads to a new subpage that
shows all sites (embedders) that the origin has or has not storage
access in.

Screenshot top-level page: http://screen/79Ru9MKzkHwnKQA
Screenshot subpage: http://screen/9ab7f7byv6zGsQc

A follow up CL will deal with the deletion of an entire group of
storage access permissions.

WebsitePreference

Low-Coverage-Reason: COVERAGE_UNDERREPORTED Refactoring in
Bug: 1478113, b:307249155
Change-Id: I5ef174f1cfdc6d6e234da07f071110cfee8221bb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5001442
Commit-Queue: Filipa Senra <fsenra@google.com>
Reviewed-by: Christian Dullweber <dullweber@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1225989}