Cleanup RadioOnHelper and supporting methods

Minor changes to comments and fixs possible bug
introduced in refactor: The phone type should
be saved before the radio is turned on in order
for the TelephonyConnectionService to switch
the phone type later if it changes when the
call is placed.

Test: Telephony Unit Tests
Change-Id: Id6c1c3299bacbb4335cb5bf62f76de7a7b90a298
5 files changed