Add ability to detect media profile changes and propagate upwards.

Changes to the media codec, bitrate and bandwidth were not detected and
propagated upwards to the dialer.  This change adds a new listener for
deltas in these attributes which will trigger updates in the
TelephonyConnectionService.

Test: Added unit test for this condition.
Fixes: 176862263
Change-Id: I4301664bdbe2576e9d95188e5e130a891d86c810