Bisects to https://chromium.googlesource.com/chromium/src/+log/6f9bcf6caf008fd582ef72bf8b88fe6984fa16bb..9c18d34fca347089da0526df01664c2bd91c2a57

So it's likely
https://chromium-review.googlesource.com/c/chromium/src/+/1000555

Before r550078, it would always print in color, right?

To answer my own question, yes. Right now, the problem is the color setting is set to UNKNOWN_COLOR_MODEL.

https://chromium-review.googlesource.com/1060384

govind: Just a heads up - we will want to merge this to M67. Previously, we always printed in color. Trying to fix that resulted in always printing in black and white in this case.

Thank you  thestig@. Pls land the fix to trunk ASAP and request a merge to M67. Pls note we only have next week Beta left after tomorrow's beta release before stable promotion.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0c4f392def5d8c7c77cdf8a9c20385be3ef2f4f9

commit 0c4f392def5d8c7c77cdf8a9c20385be3ef2f4f9
Author: Lei Zhang <thestig@chromium.org>
Date: Tue May 15 23:05:26 2018

Printing: Read the color setting from the system dialog on Windows.

BUG= 843212 

Change-Id: Iab38833fabfe1c6729c76419d50e39cfe7eb098a
Reviewed-on: https://chromium-review.googlesource.com/1060384
Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#558875}
[modify] https://crrev.com/0c4f392def5d8c7c77cdf8a9c20385be3ef2f4f9/printing/print_settings_initializer_win.cc
[modify] https://crrev.com/0c4f392def5d8c7c77cdf8a9c20385be3ef2f4f9/printing/printing_context_win_unittest.cc

rbpotter@/thestig@, Pls verify this bug on tonight's canary.

The NextAction date has arrived: 2018-05-16

Verified this on Canary 68.0.3432.0 on Windows 10 with the Xerox PS Global Print Driver. Printed the following cases using system dialog:
- HTML -> color
- HTML -> bw
- PDF -> color
- PDF -> bw
In all cases output document had the color specified by the preferences.

Thank you rbpotter@ for canary verification.

thestig@, pls request a merge to M67 if you feel it is safe to merge now. If you want little more canary baking, then it is fine to wait as well. Thank you.

This bug requires manual review: We are only 12 days from stable.
Please contact the milestone owner if you have questions.
Owners: cmasso@(Android), cmasso@(iOS), kbleicher@(ChromeOS), govind@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Approving merge to M67 branch 3396 based on comment #11 and per offline chat with thestig@, this should be a safe merge.

Pls merge and mark the bug as fixed. 

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8163f5836cb2303e6b7eb76d3b22c645473f7913

commit 8163f5836cb2303e6b7eb76d3b22c645473f7913
Author: Lei Zhang <thestig@chromium.org>
Date: Wed May 16 18:43:03 2018

M67: Printing: Read the color setting from the system dialog on Windows.

BUG= 843212 
TBR=rbpotter@chromium.org

(cherry picked from commit 0c4f392def5d8c7c77cdf8a9c20385be3ef2f4f9)

Change-Id: Iab38833fabfe1c6729c76419d50e39cfe7eb098a
Reviewed-on: https://chromium-review.googlesource.com/1060384
Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#558875}
Reviewed-on: https://chromium-review.googlesource.com/1062187
Reviewed-by: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/branch-heads/3396@{#615}
Cr-Branched-From: 9ef2aa869bc7bc0c089e255d698cca6e47d6b038-refs/heads/master@{#550428}
[modify] https://crrev.com/8163f5836cb2303e6b7eb76d3b22c645473f7913/printing/print_settings_initializer_win.cc
[modify] https://crrev.com/8163f5836cb2303e6b7eb76d3b22c645473f7913/printing/printing_context_win_unittest.cc