CHROME VERSION: 53.0.2768.0 dev
CHROMEOS_RELEASE_DESCRIPTION: 8459.0.0 (Official Build) dev-channel veyron_minnie-cheets
CHROMEOS_RELEASE_VERSION: 8459.0.0

What steps will reproduce the problem?

1. Sign in to Minnie.
2. Make sure the current physical orientation of the device is landscape.
3. Flip the keyboard to use Minnie as tablet.
4. Make sure orientation lock is currently disabled.
5. Rotate the device (physically) to use it in portrait mode.
6. Enable orientation lock.
7. [optional] Make sure the lock is working, by physically rotating the device several times.
8. Hold the device in portrait mode, long-press the physical power button to lock the device, and _while_ pressing the power button, change the physical orientation of the device back to landscape.

What is the expected output?

Orientation lock is still enabled on the lock screen, and the lock screen is displayed in portrait mode.

What do you see instead?

Orientation lock is still enabled on the lock screen, BUT the lock screen is displayed in _landscape_ mode. This is not 100% reproducible, but I think I can reproduce this once in 4 trials or so.


Please use labels and text to provide additional information.

* Sudden orientation change is annoying especially when using Minnie as an Android tablet.
* As of today, the sudden orientation change also causes b/29453379. Most ARC processes freezes because of the ARC side bug.

* Not sure if this is useful, but here is the log I uploaded right after unlocking the device:
https://feedback.corp.google.com/#/Report/10017786710