Merge change I4e83a76a into eclair

* changes:
  Fix bug 2201417. Whenever the System setting that indicates whether the notifcation stream uses the ring volume changes, the table of stream volume aliases in AudioService is updated. But the name of the alias stored in VolumeStreamState.mVolumeIndexSettingName was not updated whenever the NOTIFICATIONS_USE_RING_VOLUME setting was updated. This caused the wrong volume setting to be persisted. This change ensures the setting name is updated whenever the volume alias is, and persists the notification volume change right away (instead of after a delay), so that registered observers are notified right away. The notification seekbar in the sound settings is an example of such an observer.