"Rewrite" PhoneNumberUtil so that it compares two phone strings using as many...

"Rewrite" PhoneNumberUtil so that it compares two phone strings using as many characters as possible, unlike the previous implementation.
Unlike the change 5480, this considers the NDD-problem mentioned in the internal issue 1949010.
This time, 1-650-555-1234 and 650-555-1234 match each other.

Added tests for the cases.

related internal issue: 1868702, 1949010