Fix call stuck in ringing state

While handling incoming call, the incoming call session might be terminated.
If the call session was terminated before registering callback, framework should
not handle incoming call.

Bug: 289461637
Bug: 304441595
Test: atest ImsManagerTest
Test: received test result from partner
Change-Id: I0c9dbc0c5d048ec411ff5e7eb0ad773212813c96
1 file changed