Add logging for slow device events, limit network UI update rate

ash/system/chromeos/network/network_detailed_view.h

Index: ash/system/chromeos/network/network_detailed_view.h
diff --git a/ash/system/chromeos/network/network_detailed_view.h b/ash/system/chromeos/network/network_detailed_view.h
index 772f239cabbec16a65b9a66ff3ab13c53287b1f7..0d17c7ad5117e899098edf5a1a93c28c9e8df92b 100644
--- a/ash/system/chromeos/network/network_detailed_view.h
+++ b/ash/system/chromeos/network/network_detailed_view.h
@@ -29,17 +29,10 @@ class NetworkDetailedView : public TrayDetailsView {
 
   virtual DetailedViewType GetViewType() const = 0;
 
-  // Called when network manager state has changed.
-  // (Generic update for NetworkTray <> AshSystemTrayDelegate interface).
-  virtual void ManagerChanged() = 0;
-
-  // Called when the contents of the network list have changed.
-  // (Called only from TrayNetworkStateObserver).
-  virtual void NetworkListChanged() = 0;
-
-  // Called when a network service property has changed.
+  // Called when the contents of the network list have changed or when any
+  // Manager properties (e.g. technology state) have changed.
   // (Called only from TrayNetworkStateObserver).
-  virtual void NetworkServiceChanged(const chromeos::NetworkState* network) = 0;
+  virtual void Update() = 0;
 
  protected:
   virtual ~NetworkDetailedView() {}