Feedback report is at http://feedback/#/Report/85281152904.

Xiaohui, didn't we replace this with a toast in a recent update?

We do show it when the corp policy disables the playstore.  This instance looks weird.  ARC was enabled, but then disabled and removed after about 30s. Maybe this is a new flow/condition we are not aware of. 

Yury, do you see what's happening here?

[1309:1309:0406/152848.992970:VERBOSE1:arc_session_manager.cc(583)] ARC opt-in. Starting ARC session.
[1309:1309:0406/152848.993053:VERBOSE1:arc_session_manager.cc(745)] Use default negotiator.
[1309:1309:0406/152920.624608:VERBOSE1:arc_util.cc(365)] Google-Play-Store-enabled pref is managed. Request to disable Play Store is not stored
[1309:1309:0406/152920.624674:VERBOSE1:arc_session_runner.cc(198)] Session stop requested
[1309:1309:0406/152920.624918:VERBOSE1:arc_session_manager.cc(682)] ARC opt-out. Removing user data.
[1309:1309:0406/152920.920726:INFO:arc_session_runner.cc(270)] ARC stopped: SHUTDOWN

When I reboot I get the 'enable arc' dialog, but I hit cancel (disagree
with the terms) because I don't want arc.

mwharris@ do you see this 'enable arc' dialog every time after reboot?

Yep, every time I reboot it prompts me to enable arc. Each time I have to
hit cancel.

So from optin flow perspective it looks WAI.

1. ARC is managed and enabled. That is why optin UI is shown.
2. User presses 'Cancel' and we don't run ARC. However it still enabled.
3. Next session login - 1 is repeated (ARC is enabled)

I know, it might look bit strange but this is what was exactly requested.

I think the "arc prompt every time" is WAI, but the undismissable white box
isn't.

Thanks for the clarifications. 

khmel@, how can we detect this case?  Currently we check the kArcEnabled pref and it seems to return true in this case. 
https://cs.chromium.org/chromium/src/chrome/browser/chromeos/arc/arc_util.cc?rcl=484c9c56d0ea555df728ff7fa9fd777069378d49&l=583

CL: crrev.com/c/1019348 

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/122eb4f7a87f28eb1f8c81d3318a3a07a265f721

commit 122eb4f7a87f28eb1f8c81d3318a3a07a265f721
Author: khmel@google.com <khmel@google.com>
Date: Thu Apr 19 17:30:37 2018

arc: Fix assistant activation logic.

This CL fixes following issues:
Assistant has dependencies on ARC and it has to count them when
checked for activation. This uses default helper
IsArcTermsOfServiceOobeNegotiationNeeded to determine that ARC
is not Opted-In.
This also changes direct prefs::kArcEnabled manipulation to helper
SetArcPlayStoreEnabledForProfile that has logic to start arc session
when needed besides only setting that flag.

Test: Manually
Bug:  831302 
Change-Id: I48ce9400d668052bff7691deed42b7bdeb777827
Reviewed-on: https://chromium-review.googlesource.com/1019348
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Yury Khmel <khmel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#552062}
[modify] https://crrev.com/122eb4f7a87f28eb1f8c81d3318a3a07a265f721/chrome/browser/chromeos/arc/voice_interaction/arc_voice_interaction_framework_service.cc
[modify] https://crrev.com/122eb4f7a87f28eb1f8c81d3318a3a07a265f721/chrome/browser/chromeos/login/wizard_controller.cc
[modify] https://crrev.com/122eb4f7a87f28eb1f8c81d3318a3a07a265f721/chrome/browser/ui/webui/chromeos/login/arc_terms_of_service_screen_handler.cc