Move code in src/remoting to the new callbacks.

remoting/host/disconnect_window_linux.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "remoting/host/disconnect_window.h"
 
 #include <gtk/gtk.h>
 
 #include "base/compiler_specific.h"
 #include "base/logging.h"
@@ skipping 102 matching lines @@
     disconnect_window_ = NULL;
   }
 }
 
 void DisconnectWindowLinux::OnResponse(GtkWidget* dialog, int response_id) {
   // |response_id| is ignored, because there is only one button, and pressing
   // it should have the same effect as closing the window (if the window Close
   // button were visible).
   CHECK(host_);
 
-  host_->Shutdown(NULL);
+  host_->Shutdown(base::Closure());
   Hide();
 }
 
 DisconnectWindow* DisconnectWindow::Create() {
   return new DisconnectWindowLinux;
 }
 
 }  // namespace remoting