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

remoting/host/host_script_object.cc

Index: remoting/host/host_script_object.cc
diff --git a/remoting/host/host_script_object.cc b/remoting/host/host_script_object.cc
index dab16d1a0a5698387904fce1d78f70f8d2412939..0808066dfbb82330ec7df3e3ef188585f62a654a 100644
--- a/remoting/host/host_script_object.cc
+++ b/remoting/host/host_script_object.cc
@@ -283,6 +283,11 @@ void HostNPScriptObject::OnAccessDenied() {
     DisconnectInternal();
 }
 
+void HostNPScriptObject::OnAuthenticatedClientsChanged(int clients_connected) {
+  DCHECK_NE(base::PlatformThread::CurrentId(), np_thread_id_);
+  OnStateChanged(clients_connected ? kConnected : kDisconnected);
+}
+
 void HostNPScriptObject::OnShutdown() {
   DCHECK_EQ(MessageLoop::current(), host_context_.main_message_loop());