If available we use the current network mcc to get the list of emergency numbers. This gives us a fallback when there's no information on the SIM. While at that add the EU countries as they all support 112
Several topics should be considered:
emergency-numbers-changed when we update the origin's country code is not 100% clean, we could add an extra signal
EMERGENCY_CALL_ORIGIN interface to group more of these functions (could also be follow up, just wanted to mention that we keep bolting onto the origin interface).
Helps #574 as we at least support SIMs now that don't have any emergency numbers stored
This should make emergency calling useful for way more people.