Interface provides location information to the nsGeolocator
 via the nsIDOMGeolocationCallback interface.  After
 startup is called, any geo location change should call
 callback.onRequest().
[scriptable, uuid(5c819505-8804-496e-9cb2-53089b3dd4ef)]
interface nsIGeolocationProvider : nsISupports

Methods

 Returns true when the devices is ready and has a
 postion, otherwise false.
boolean isReady() 
 shutdown
 Shuts down the location device.
void shutdown() 
 Start up the provider.  This is called before any other
 method.  may be called multiple times.
void startup() 
 watch
 When a location change is observed, notify the callback
void watch(in nsIGeolocationUpdate callback)