Add SessionStateObserver with ActiveUserChanged()

chrome/browser/chromeos/system/ash_system_tray_delegate.cc

 // Copyright (c) 2012 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/chromeos/system/ash_system_tray_delegate.h"
 
 #include <algorithm>
 #include <set>
 #include <string>
 #include <vector>
 
 #include "ash/ash_switches.h"
 #include "ash/desktop_background/desktop_background_controller.h"
+#include "ash/session_state_delegate.h"
+#include "ash/session_state_observer.h"
 #include "ash/shell.h"
 #include "ash/shell_delegate.h"
 #include "ash/shell_window_ids.h"
 #include "ash/system/bluetooth/bluetooth_observer.h"
 #include "ash/system/brightness/brightness_observer.h"
 #include "ash/system/chromeos/audio/audio_observer.h"
 #include "ash/system/chromeos/network/network_observer.h"
 #include "ash/system/chromeos/network/network_tray_delegate.h"
 #include "ash/system/date/clock_observer.h"
 #include "ash/system/drive/drive_observer.h"
@@ skipping 204 matching lines @@
                            public SessionManagerClient::Observer,
                            public NetworkLibrary::NetworkManagerObserver,
                            public drive::JobListObserver,
                            public content::NotificationObserver,
                            public input_method::InputMethodManager::Observer,
                            public system::TimezoneSettings::Observer,
                            public chromeos::SystemClockClient::Observer,
                            public device::BluetoothAdapter::Observer,
                            public SystemKeyEventListener::CapsLockObserver,
                            public ash::NetworkTrayDelegate,
-                           public policy::CloudPolicyStore::Observer {
+                           public policy::CloudPolicyStore::Observer,
+                           public ash::SessionStateObserver {
  public:
   SystemTrayDelegate()
       : ui_weak_ptr_factory_(
           new base::WeakPtrFactory<SystemTrayDelegate>(this)),
         user_profile_(NULL),
         clock_type_(base::k24HourClock),
         search_key_mapped_to_(input_method::kSearchKey),
         screen_locked_(false),
         have_session_start_time_(false),
         have_session_length_limit_(false),
@@ skipping 53 matching lines @@
 
     system::TimezoneSettings::GetInstance()->AddObserver(this);
     DBusThreadManager::Get()->GetSystemClockClient()->AddObserver(this);
 
     if (SystemKeyEventListener::GetInstance())
       SystemKeyEventListener::GetInstance()->AddCapsLockObserver(this);
 
     device::BluetoothAdapterFactory::GetAdapter(
         base::Bind(&SystemTrayDelegate::InitializeOnAdapterReady,
                    ui_weak_ptr_factory_->GetWeakPtr()));
+
+    ash::Shell::GetInstance()->session_state_delegate()->
+        AddSessionStateObserver(this);
   }
 
   virtual void Shutdown() OVERRIDE {
     data_promo_notification_.reset();
   }
 
   void InitializeOnAdapterReady(
       scoped_refptr<device::BluetoothAdapter> adapter) {
     bluetooth_adapter_ = adapter;
     CHECK(bluetooth_adapter_);
@@ skipping 945 matching lines @@
 
   // Overridden from CloudPolicyStore::Observer
   virtual void OnStoreLoaded(policy::CloudPolicyStore* store) OVERRIDE {
     UpdateEnterpriseDomain();
   }
 
   virtual void OnStoreError(policy::CloudPolicyStore* store) OVERRIDE {
     UpdateEnterpriseDomain();
   }
 
+  // Overridden from ash::SessionStateObserver
+  virtual void ActiveUserChanged(const std::string& user_id) OVERRIDE {
+    GetSystemTrayNotifier()->NotifyUserUpdate();
+  }
+
   void UpdateCellular() {
     const CellularNetworkVector& cellular_networks =
         CrosLibrary::Get()->GetNetworkLibrary()->cellular_networks();
     if (cellular_networks.empty())
       return;
     // We only care about the first cellular network (in practice there will
     // only ever be one)
     const CellularNetwork* cellular = cellular_networks[0];
     if (cellular->activation_state() == ACTIVATION_STATE_ACTIVATING) {
       cellular_activating_ = true;
@@ skipping 38 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(SystemTrayDelegate);
 };
 
 }  // namespace
 
 ash::SystemTrayDelegate* CreateSystemTrayDelegate() {
   return new chromeos::SystemTrayDelegate();
 }
 
 }  // namespace chromeos