I'm going to steal since I'm looking at the flow right now.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/platform2/+/d53c85f1c073ba0835e4cf90b316a50e0d5bd02a

commit d53c85f1c073ba0835e4cf90b316a50e0d5bd02a
Author: Sean Kau <skau@chromium.org>
Date: Thu Dec 01 00:17:57 2016

debugd: Fix segment count for the PPDCache folder.

The file name is included in the segment count so it should
be increased to six.

BUG= chromium:670037 
TEST=Add a printer with the dbus client using a PPDCache path.
Change-Id: Ia9ad576667cdb36eca3aa3dd907d21db28b28b7c
Reviewed-on: https://chromium-review.googlesource.com/415430
Commit-Ready: Sean Kau <skau@chromium.org>
Tested-by: Sean Kau <skau@chromium.org>
Reviewed-by: Justin Carlson <justincarlson@google.com>
Reviewed-by: Mike Frysinger <vapier@chromium.org>

[modify] https://crrev.com/d53c85f1c073ba0835e4cf90b316a50e0d5bd02a/debugd/src/cups_tool.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9b008b2277810ec4638488b3bfe2fd2ef5b85eb7

commit 9b008b2277810ec4638488b3bfe2fd2ef5b85eb7
Author: skau <skau@chromium.org>
Date: Wed Dec 07 22:09:24 2016

Hookup the PpdProvider in the printer setup flow.

Cache manually added PPDs and lookup PPDs with the provider in the
add printer dialog.

BUG= 670037 

Review-Url: https://codereview.chromium.org/2545663002
Cr-Commit-Position: refs/heads/master@{#437078}

[modify] https://crrev.com/9b008b2277810ec4638488b3bfe2fd2ef5b85eb7/chrome/browser/ui/webui/print_preview/printer_backend_proxy_chromeos.cc
[modify] https://crrev.com/9b008b2277810ec4638488b3bfe2fd2ef5b85eb7/chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.cc
[modify] https://crrev.com/9b008b2277810ec4638488b3bfe2fd2ef5b85eb7/chrome/browser/ui/webui/settings/chromeos/cups_printers_handler.h
[modify] https://crrev.com/9b008b2277810ec4638488b3bfe2fd2ef5b85eb7/chromeos/printing/printer_configuration.cc
[modify] https://crrev.com/9b008b2277810ec4638488b3bfe2fd2ef5b85eb7/chromeos/printing/printer_configuration.h

User specified PPDs are now saved in the PPDCache folder.