The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/94f1b555f210e16ee005981f2fa4674db31e6aee

commit 94f1b555f210e16ee005981f2fa4674db31e6aee
Author: Justin Carlson <justincarlson@chromium.org>
Date: Wed Nov 15 21:08:05 2017

Small CupsPrintersManager refactor.

Pull notifications into a function so that it's harder to have a
bug like crbug/764976 (already fixed in another cl) in which a
notification is given to the wrong set of printers.

Along the way, fix a code path in which notification were generated
too many times -- when the Configured printer set was changed, we
would notify twice (once in UpdateConfiguredPrintersURIs and again
in OnConfiguredPrintersChanged).  This was harmless, but wasteful.

Kudos to Vladislav Kuzkokov for noticing an incorrect line
that led to this change.

Bug:  764976 
Change-Id: I68d6c1d1fd90a7756adefbc29aed4004be05da24
Reviewed-on: https://chromium-review.googlesource.com/770092
Reviewed-by: Sean Kau <skau@chromium.org>
Commit-Queue: Justin Carlson <justincarlson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#516826}
[modify] https://crrev.com/94f1b555f210e16ee005981f2fa4674db31e6aee/chrome/browser/chromeos/printing/cups_printers_manager.cc