Fix empty network type list in triggerEmergencyNetworkScan

If a carrier doesn't support CS emergency calls and dialing IMS call has
failed, then triggerEmergencyNetworkScan is invoked with empty network
type list.

Bug: 266030361
Test: atest EmergencyCallDomainSelectorTest
Change-Id: I844bf9387a20b44ed967f020b84bcb941182d723
2 files changed