Enhancements to conference for non-conference host scenarios.

When a device A creates a conference call containing device B and C, both
B and C can receive IMS signaling to indicate that they are in a conference
call.  This occurs on most domestic carriers; the Telephony framework
uses the "multiparty" indicator on the IMS call to switch the call to a
conference call.

We made some changes to how conference calls are logged in Q which improves
the accuracy of the call durations.  We used to log calls as they're merged
into a conference.  In the case of a participant in a remotely hosted
conference call, we'd log the call as soon as they are remotely added
to the conference.  This is unfortunate as the call durations are grossly
under-reported.

The conference call logging changes now assume we'll log the conference
event package children in the conference instead of the participants which
merge into the conference itself.  On domestic carriers, since the
call on B (or C) becomes a conference, we would then no longer log the
call.

This is FURTHER complicated because on some carriers, B and C will ALSO
receive a conference event package from the network showing all the
participants in the conference.  So if B hangs up on the conference, they
will have entries in their call log for A and C, which is really strange
because a call to C was never originated on their device.

In Telecom we need to ensure we do not log remotely hosted conference
participants, and we need to ensure that we DO log a remotely hosted
conference as if its just a single party call.

To accomplish this we need:
1. Telecom needs to track the address and name display for remotely hosted
conferences; this ensures we can log the remotely hosted conference
correctly.
2. Telecom needs to track whether a conference call had children or not;
if it had children it should not be logged.  If it did not have children
and it was remotely hosted it should be logged.

Test: Manual test.
Test: Add unit test to cover this logging scenario.
Bug: 132325382
Change-Id: I7ab193d2c4252b6a97c27ee81cdd7ae152b505fb