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- This CL is in anticipation of the Show More feature to be implemented
  for Saved printers.
- The behavior of CupsPrintersEntryList will soon have customized
  features for saved printers.
- CupsSavedPrinters and CupsNearbyPrinters will now have their own list
  to manage.

Bug: 993822
Test: end to end manual, browsertest
Change-Id: I58d9f4a9920decbb5f4eab23505be52d962e90a8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1835703Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Reviewed-by: Bailey Berro <baileyberro@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: jimmy gong <jimmyxgong@chromium.org>
Cr-Commit-Position: refs/heads/master@{#706132}