Implement UI hookups for notifying users of a EULA for a printer

- Users will be notified if their printer has an EULA with a text in the
  edit and manfacturer/model dialog.
- Checking if a EULA exist for a printer is handled in
  cups_printers_handler.
- Added browserTests to reflect this change.

Bug: 943634
Test: End to End, browser tests

Change-Id: Iaa882bd2f51dcd78763a4eace9c1d69b8cb544f0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1585322
Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Reviewed-by: Bailey Berro <baileyberro@chromium.org>
Commit-Queue: jimmy gong <jimmyxgong@chromium.org>
Cr-Commit-Position: refs/heads/master@{#661562}
12 files changed