UserAgent: Mozilla/5.0 (X11; CrOS x86_64 10176.76.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.190 Safari/537.36

Steps to reproduce the problem:
1. create a sample kiosk app
2. add permission networking.onc in manifest file
3. add some get request of networkin.onc in background.js
4. Run the app in chromebook
5. getting error on console: Cannot read property 'onc' of undefined

What is the expected behavior?
networking.onc should be able to identified as an API

What went wrong?
networking.onc API is not working

Did this work before? N/A 

Does this work in other browsers? N/A

Chrome version: 64.0.3282.190  Channel: dev
OS Version: 10176.76.0
Flash Version: