Delete geofencing implementation.

third_party/WebKit/LayoutTests/http/tests/geofencing/resources/worker-passes-events-back.js

-var port;
-
-self.addEventListener('message', function(event) {
-  port = event.data.port;
-  port.postMessage('setup');
-});
-
-self.addEventListener('geofenceenter', function(event) {
-  port.postMessage({event: 'geofenceenter', id: event.region.id});
-});
-
-self.addEventListener('geofenceleave', function(event) {
-  port.postMessage({event: 'geofenceleave', id: event.region.id});
-});