Determine the name advertised as a Google Cast destination.
If this policy is set to a non empty string, that string will be used as the name of the Google Cast destination. Otherwise, the destination name will be the device name. If this policy is not set, the destination name will be the device name, and the owner of the device (or a user from the domain managing the device) will be allowed to change it. The name is limited to 24 characters.