[MediaRouter] Record DIAL device counts in DialMediaSinkServiceImpl

chrome/browser/media/router/discovery/dial/dial_media_sink_service_impl.h

Index: chrome/browser/media/router/discovery/dial/dial_media_sink_service_impl.h
diff --git a/chrome/browser/media/router/discovery/dial/dial_media_sink_service_impl.h b/chrome/browser/media/router/discovery/dial/dial_media_sink_service_impl.h
index d84a64c9805dc8d509d1b8a62a89247da945736a..4f07bfc0a9c7ce108f82f2e550d61d3febc3f69d 100644
--- a/chrome/browser/media/router/discovery/dial/dial_media_sink_service_impl.h
+++ b/chrome/browser/media/router/discovery/dial/dial_media_sink_service_impl.h
@@ -63,6 +63,9 @@ class DialMediaSinkServiceImpl : public MediaSinkServiceBase,
   void OnDeviceDescriptionError(const DialDeviceData& device,
                                 const std::string& error_message);
 
+  // MediaSinkServiceBase implementation.
+  void RecordDeviceCounts() override;
+
   std::unique_ptr<DeviceDescriptionService> description_service_;
 
   // Raw pointer to DialRegistry singleton.
@@ -75,6 +78,8 @@ class DialMediaSinkServiceImpl : public MediaSinkServiceBase,
   DialRegistry::DeviceList current_devices_;
 
   scoped_refptr<net::URLRequestContextGetter> request_context_;
+
+  base::Time device_count_metrics_record_time_;
 };
 
 }  // namespace media_router