UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36

Steps to reproduce the problem:
reported in https://partnerissuetracker.corp.google.com/issues/72749130

1. get a chromebook(dru/scarlet/cyan) with tablet mode enabled
2. in OOBE, enable ChromeVox  
3. rotate to any other rotations(90/180/270)
4. try to touch anything on the screen

What is the expected behavior?
touch event works

What went wrong?
touch event not working, and there's a notify sound(but don't know what is it notifying)

Did this work before? N/A 

Chrome version:   Channel: stable
OS Version: R66-10359.0.0
Flash Version: 

rotation 0 works well.