am c5ab362a: Add a setting to change the default ringtone.

Merge commit 'c5ab362aa8bd98d8a160a72dc8790103b9d6596f' into eclair-mr2-plus-aosp

* commit 'c5ab362aa8bd98d8a160a72dc8790103b9d6596f':
  Add a setting to change the default ringtone.