Detect invalid Call Forwarding numbers and replace

When there is an invalid Call Forwarding number
returned by the network from a query, optionally
replace the invalid number with "Voicemail". This
option is controlled by a new carrier config
option
KEY_CALL_FORWARDING_MAP_NON_NUMBER_TO_VOICEMAIL_BOOL.

Bug: 67267077
Test: Manual
Change-Id: I3ce36278790e8f09c1ee26c1b85d652efbcd025a
3 files changed