This patch includes the plus code conversion clean up.
1. change the plus code conversion based on the current and default
number systems retrieved from MCC.
2. for format such as +NANP, replace the '+' with the current IDP (011).
3. comments changes.
The issue is that the plus sign in a dial string is always converted
to the IDP (International Dial Prefix).
This fix implements a plus sign conversion mechanism based on the default
telephone numbering system that the phone is activated and the current telephone
number system that the phone is camped on. Currently, we only support the cases
where the default and current telephone numbering system are NANP.
This method is used by the Phone app to decode ACTION_CALL
Intents, resolving to a real phone number. Because the
columns are changing with the new provider, I added logic
to query using the correct columns for the authority of the
requested Uri.
