In the meantime, I suggest just not logging CanMakePayment related metrics while in Incognito mode.

Incognito mode behavior of web payments API:
1) PaymentRequest.canMakePayments() never returns false.
2) PaymentRequest.show() never returns NotSupportedError.

My first idea would be to simply not record those, since the result is always the same. It might screw up the rest of our metrics.

However, if the number of people using PR in incognito is high enough, we will want to have their metrics too.

Therefore, I think we should split the CMP histograms in two with the suffix _inIncognitoMode or something.

WDYT?

Oops, I just realized you are not talking about metrics... Doing metrics all day will do that to you :P sorry

Better to not record in incognito at all rather than record incognito metrics separately, IMHO.

created  crbug.com/704689  to continue the metrics discussion.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/f39f46dcb8679cf14ccd7ff0cf205de49edea458

commit f39f46dcb8679cf14ccd7ff0cf205de49edea458
Author: mathp <mathp@chromium.org>
Date: Fri Mar 24 22:08:52 2017

[Payments] Desktop: never return false in incognito mode for canMakePayment

BUG= 704675 
TEST=browser_tests

Review-Url: https://codereview.chromium.org/2772103002
Cr-Commit-Position: refs/heads/master@{#459570}

[modify] https://crrev.com/f39f46dcb8679cf14ccd7ff0cf205de49edea458/chrome/browser/payments/chrome_payment_request_delegate.cc
[modify] https://crrev.com/f39f46dcb8679cf14ccd7ff0cf205de49edea458/chrome/browser/payments/chrome_payment_request_delegate.h
[modify] https://crrev.com/f39f46dcb8679cf14ccd7ff0cf205de49edea458/chrome/browser/ui/views/payments/payment_request_browsertest_base.cc
[modify] https://crrev.com/f39f46dcb8679cf14ccd7ff0cf205de49edea458/chrome/browser/ui/views/payments/payment_request_browsertest_base.h
[modify] https://crrev.com/f39f46dcb8679cf14ccd7ff0cf205de49edea458/chrome/browser/ui/views/payments/payment_request_can_make_payment_browsertest.cc
[modify] https://crrev.com/f39f46dcb8679cf14ccd7ff0cf205de49edea458/chrome/browser/ui/views/payments/test_chrome_payment_request_delegate.cc
[modify] https://crrev.com/f39f46dcb8679cf14ccd7ff0cf205de49edea458/chrome/browser/ui/views/payments/test_chrome_payment_request_delegate.h
[modify] https://crrev.com/f39f46dcb8679cf14ccd7ff0cf205de49edea458/components/payments/content/payment_request.cc
[modify] https://crrev.com/f39f46dcb8679cf14ccd7ff0cf205de49edea458/components/payments/content/payment_request_delegate.h
[modify] https://crrev.com/f39f46dcb8679cf14ccd7ff0cf205de49edea458/components/payments/content/payment_request_state.cc