Add a battery icon to the right of Tether networks in system tray.

ash/system/network/network_list.h

Index: ash/system/network/network_list.h
diff --git a/ash/system/network/network_list.h b/ash/system/network/network_list.h
index 3eca162a47f996a8c7ab0d2d2b1b29d7755fe3ce..7fcd2d448b54ea48462d919d03104e08e44edd5e 100644
--- a/ash/system/network/network_list.h
+++ b/ash/system/network/network_list.h
@@ -73,6 +73,11 @@ class NetworkListView : public NetworkStateListDetailedView,
   // Updates |view| with the information in |info|.
   void UpdateViewForNetwork(HoverHighlightView* view, const NetworkInfo& info);
 
+  // Creates the a battery icon next to the name of Tether networks indicating
+  // the battery percentage of the mobile device that is being used as a
+  // hotspot.
+  views::View* CreatePowerStatusView(const NetworkInfo& info);
+
   // Creates the view of an extra icon appearing next to the network name
   // indicating that the network is controlled by an extension. If no extension
   // is registered for this network, returns |nullptr|.