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- When there is no connectivity, we disable the ability to add a
  printer and display a message to users.

Bug: 993834
Test: browser tests, end to end manual
Change-Id: I6f0eb28bcd2df604c8e27e799df239a646d0119a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1761482
Commit-Queue: jimmy gong <jimmyxgong@chromium.org>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Reviewed-by: Bailey Berro <baileyberro@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#690952}