Hang up active call based on emergency call domain

If AP domain selection is enabled and an emergency call is connected to
other domain during an active call, there is a problem in which the
existing active call is not disconnected.
This change is intended to allow outgoing emergency call to continue to
be processed after first disconnecting the active calls before making an
emergency call over other domain.

Bug: 391287237
Flag: com.android.internal.telephony.flags.hangup_active_call_based_on_emergency_call_domain
Test: atest TelephonyConnectionServiceTest
Test: manual (verified the active call is disconnected on other domain
first before an emergency call is being processed)

Change-Id: Id8fb96dfd8c83e1636a8b8cac5e30f04f50668e2
2 files changed