Helper methods for voicemail status provider.

Added method to make it easier to insert into the voicemail status
table. Also takes in a phone account for future multi-SIM support.

Remove VvmSyncService class in favor of moving most of the code to
OmtpVvmSyncService.

Bug: 19236241
Change-Id: I5d9def276fbdbc6f825fb35e9fa31bfc3cead1ba
4 files changed