Notify calling web-app when Host plugin becomes connected to a client.

remoting/host/host_status_observer.h

Index: remoting/host/host_status_observer.h
diff --git a/remoting/host/host_status_observer.h b/remoting/host/host_status_observer.h
index dd0ae8599c06ff0117237696355e4a06d484165b..daecba34171c8ee9e0dd473de89a07cd7c23e759 100644
--- a/remoting/host/host_status_observer.h
+++ b/remoting/host/host_status_observer.h
@@ -21,6 +21,11 @@ class HostStatusObserver
                                      const std::string& full_jid) = 0;
   virtual void OnSignallingDisconnected() = 0;
 
+  // Called on the main thread when a client authenticates, or disconnects.
+  // The observer must not tear-down ChromotingHost state on receipt of
+  // this callback; it is purely informational.
+  virtual void OnAuthenticatedClientsChanged(int authenticated_clients) = 0;

[Jamie, 2011/06/10 18:00:38]

Optional: I think that this method is never implemented if the other three are,
and vice versa. Perhaps a separate interface would be better.

[Wez, 2011/06/13 20:30:35]

That certainly makes sense, but currently HostStatusObserver is RefCounted.  I'd
like to fix it to be a pure observer interface before splitting it up.

+
   // Called on the main thread when the host shuts down.
   virtual void OnShutdown() = 0;