shill: Add method for querying geolocation objects on a device.

Currently, only WiFi is implemented.

BUG=chromium-os:34844
TEST=unit test

Change-Id: I1ef485162052af3165da71fb170940f617e4f071
Reviewed-on: https://gerrit.chromium.org/gerrit/35975
Reviewed-by: Paul Stewart <pstew@chromium.org>
Commit-Ready: Gaurav Shah <gauravsh@chromium.org>
Tested-by: Gaurav Shah <gauravsh@chromium.org>
diff --git a/metrics.h b/metrics.h
index a6c8cf8..ec40c2e 100644
--- a/metrics.h
+++ b/metrics.h
@@ -19,6 +19,7 @@
 
 namespace shill {
 
+class WiFiMainTest;
 class WiFiService;
 
 class Metrics {
@@ -321,6 +322,7 @@
   FRIEND_TEST(MetricsTest, TimeToPortal);
   FRIEND_TEST(MetricsTest, WiFiServiceChannel);
   FRIEND_TEST(MetricsTest, WiFiServicePostReady);
+  FRIEND_TEST(WiFiMainTest, GetGeolocationObjects);
 
   typedef ScopedVector<chromeos_metrics::TimerReporter> TimerReporters;
   typedef std::list<chromeos_metrics::TimerReporter *> TimerReportersList;