GeolocationDelegate is a pseudo interface overriden by Geolocation 
embedders [1] to provide specific functionality; it is injected via a
static SetGeolocationDelegate() method [2] which holds on to it as a
leaky-singleton.

This situation is preventing the geolocation code to be fully enclosed 
in a mojo boundary and is thus blocking  https://crbug.com/709301  (the
Geolocation servicification bug). 



[1] https://cs.chromium.org/search/?q=device::GeolocationDelegate&type=cs
[2] https://cs.chromium.org/search/?q=GeolocationProvider::SetGeolocationDelegate&type=cs