Properly route rejection reply when capability is set.

The telephony stack can be present on devices that do not have a cellular
radio. For example, connections can be established over wifi. In these
scenarios, having the replies handled by the default sms app is not
sufficient.

This CL works in conjunction with a framework change to allow connections
to mark themselves as capable of handling reply messages. In this case,
the call should route the reply back to the connection rather than have it
handled through sms.

Change-Id: I26a13496e3cff596ba950bf9abed35c36b917721