agreed, we should hide all apps which don't have content offline. The only app that has offline splash page is Play Store. Remaining apps should be hidden from shelf when device is offline. 

IIUC, we want to dynamically show/hide the Youtube app in shelf based on the current network status. It should not depend on the enrollment type.

I vote that we decide at the start of the session, rather than changing the pinned apps whenever we connect/disconnect to a network. This would be simpler for us and less intrusive to the user.

Currently, we do have this check at the start of the session (but we don't apply it to YouTube because it's a default app IIRC): https://cs.chromium.org/chromium/src/chrome/browser/chromeos/login/demo_mode/demo_session.cc?type=cs&sq=package:chromium&g=0&l=340