Replace TelephonyManager methods for mobile data

TelephonyManager had a minor refactor of some of the methods revolving
around mobile data. Change code in Settings to use the new ones instead.

Exempt-From-Owner-Approval: Cherry-picked from internal
Bug: 169367013
Test: existing unit tests, manual
Change-Id: I7ebae37373d53fb2c59b6b546232dbddf77398d4
Merged-In: I7ebae37373d53fb2c59b6b546232dbddf77398d4