Add SessionStateObserver with ActiveUserChanged()

chrome/browser/ui/ash/session_state_delegate_views.cc

 // Copyright (c) 2013 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 "chrome/browser/ui/ash/session_state_delegate.h"
 
 #include "base/logging.h"
 #include "base/string16.h"
 #include "base/utf_string_conversions.h"
 #include "ui/gfx/image/image_skia.h"
@@ skipping 55 matching lines @@
 }
 
 void SessionStateDelegate::GetLoggedInUsers(
     ash::UserEmailList* users) {
   NOTIMPLEMENTED();
 }
 
 void SessionStateDelegate::SwitchActiveUser(const std::string& email) {
   NOTIMPLEMENTED();
 }
+
+void SessionStateDelegate::AddSessionStateObserver(
+    ash::SessionStateObserver* observer) {
+  NOTIMPLEMENTED();
+}
+
+void SessionStateDelegate::RemoveSessionStateObserver(
+    ash::SessionStateObserver* observer) {
+  NOTIMPLEMENTED();
+}