Saving the contactSpecificRingtone after remote lookup

- Remote contact lookup was overwriting the cached contact specific
  ringtone. This resulted in a longer wait time for the ringtone to
  play since it would require the contact lookup to complete again.
- This CL prevents the cached ringtone from being overwritten.

Change-Id: I0a1cb30acd3aaf540533429c01427b185a7acf66