Support CDMA emergency callback. (1/2)

1. Update emergency callback mode notification icon and update creation of
the notification to use a builder.
2. For CDMA calls, if phone is in ECM mode, disable mute in the
Connection PhoneCapabilities.

Bug: 16182748
Change-Id: I698eb7d377346467fc4b87a0bec53d89f96797b1
26 files changed