UserAgent: Mozilla/5.0 (X11; CrOS x86_64 11021.81.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.110 Safari/537.36
Platform: 11021.81.0 (Official Build) stable-channel eve

Steps to reproduce the problem:
1. Have Google Pixelbook
2. Have Android Apps installed (Outlook and Skype are two culprits)
3. Enable "Do Not Disturb" mode
4. Observe as you get emails (outlook) or messages (skype) you will still get their audible notifications which will interrupt audio to play the notification noise

What is the expected behavior?
As a user the perception of the "Do Not Disturb" feature is that it will prevent notifications of any kind on my system regardless if their source is ChromeOS (websites), Android Apps, or Linux Apps.  Since ChromeOS and Android Apps are "in scope" for Google the expectation is that this will work always.  If Linux apps break this notification model because they are using some non-standard notification scheme that is acceptable.  

What went wrong?
As a user with a Pixelbook that is used at Work and at Home I am unable to disable all notifications while presenting in the job setting and viewing youtube/netflix content in the home setting.  The result is I have to dive into whatever app is causing notifications and either disable them in the app or uninstall the app temporarily.

Did this work before? N/A 

Chrome version: 70.0.3538.110  Channel: stable
OS Version: 11021.81.0
Flash Version: 31.0.0.148