Comment 0 for bug 2004634

* Impact

The current UI allows the user to try to register to Ubuntu Pro even when the system isn't online, which eventually leads to an error since the client fails to contact the server. The updated design disable the registration UI in those cases and inform the user they need to get online to be able to register which is a better experience.

* Test Case

- ensure that the machine isn't attached to ubuntu pro (otherwise the screen would not be displayed) and is online
$ pro status
and `$ pro detach` if needed

- disconnect the system, using for example the top panel indicator

- start software-properties-gtk and select the Ubuntu Pro tab

- click 'Enable Ubuntu Pro'

- The dialog controls should be disabled and a string 'Unable to connect to Ubuntu Pro servers. Check your internet connection.' displayed at the bottom

- reconnect the system

- the dialog control should become active and the label be removed

- register to Ubuntu Pro, that should be working

* Regression potential

If the connectivity check was wrong or not reliable it could be that the dialog controls would be disabled even if the system is online, or that it would fail to detect that the system isn't connected and let the user try to register anyway.