Do you know whether this is a recent regression? I have been doing some cleanup in that code, but it doesn't look like it should affect isOobeUi().

It is a recent regression. Keyboard accelerators were working for me on ToT synced around Wednesday last week and they do not work on ToT that I synced today in the morning. 

Then there's a reasonable chance it was this CL which landed over the weekend:
https://chromium-review.googlesource.com/1080227

I'll take a look. Can you point to where the call to isOobeUi() is failing?

Any call that is inside handleAccelerator() https://cs.chromium.org/chromium/src/ui/login/display_manager.js?rcl=56a6262f1826f71e8426642a498bc0bca92cebbb&l=416

You can repro by trying keycombo crtl+alt+shift+d. It should show dialog to set device requisition string:

https://cs.chromium.org/chromium/src/ui/login/display_manager.js?rcl=56a6262f1826f71e8426642a498bc0bca92cebbb&l=455 

Hmm. The dialog shortcut (ctrl-alt-shift-d) seems to be working fine for me with a ToT build from today, and Oobe.getInstance().isOobeUI() from the console returns true as I would expect.

Oobe.getInstance().isOobeUI() also returns true for me in the initial 'Welcome!' screen when running on linux with:

--user-data-dir=/tmp/chrome --login-profile=user --login-manager

Can you confirm the problem, check the console for any error messages, and include a copy of your args.gn if this is still failing?

I feel like it might be another problem, when accelerators are not handled properly if status tray menu is opened. Could this be the case?

Basically, if you disable (broken) new status tray menu, will accelerators work?

1. It works on Linux (I didn't check it before) 

2. It does not work on device: eve 69.0.3465.0 Platform 10791.0.0

3. On device I do not see any unusual errors [*]

[4614:4614:0618/160258.226272:ERROR:input_method_manager_impl.cc(1081)] IMEEngine for "jkghodnilhceideoidjikpgommlajknk" is not registered
[4686:4692:0618/160258.275251:ERROR:drm_gpu_display_manager.cc(209)] There is no display with ID 21692109949126656
[4614:4614:0618/160258.291945:ERROR:device_event_log_impl.cc(159)] [16:02:58.291] Network: network_handler_callbacks.cc:84 SetHostname Failed: Manager: org.chromium.flimflam.Error.InvalidProperty: Property HostName does not exist.
[4686:4692:0618/160258.310979:ERROR:drm_gpu_display_manager.cc(209)] There is no display with ID 21692109949126656
[4614:4614:0618/160258.312371:ERROR:device_event_log_impl.cc(159)] [16:02:58.312] Network: network_handler_callbacks.cc:84 SetHostname Failed: Manager: org.chromium.flimflam.Error.InvalidProperty: Property HostName does not exist.
[4614:4614:0618/160258.313297:ERROR:device_event_log_impl.cc(159)] [16:02:58.313] Network: network_handler_callbacks.cc:84 SetHostname Failed: Manager: org.chromium.flimflam.Error.InvalidProperty: Property HostName does not exist.
[4686:4692:0618/160258.347366:ERROR:drm_gpu_display_manager.cc(209)] There is no display with ID 21692109949126656

I flashed eve Platform 10798.0.0 from goldeneye and the issue is gone, so I am closing.