Asynchronously load wallpapers when user pod is selected.

chrome/browser/ui/webui/chromeos/login/signin_screen_handler.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/ui/webui/chromeos/login/signin_screen_handler.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/command_line.h"
@@ skipping 422 matching lines @@
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback("offlineLogin",
       base::Bind(&SigninScreenHandler::HandleOfflineLogin,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback("showAddUser",
       base::Bind(&SigninScreenHandler::HandleShowAddUser,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback("shutdownSystem",
       base::Bind(&SigninScreenHandler::HandleShutdownSystem,
                  base::Unretained(this)));
+  web_ui()->RegisterMessageCallback("userSelectedDelayed",
+      base::Bind(&SigninScreenHandler::HandleUserSelected,
+                 base::Unretained(this)));
   web_ui()->RegisterMessageCallback("removeUser",
       base::Bind(&SigninScreenHandler::HandleRemoveUser,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback("toggleEnrollmentScreen",
       base::Bind(&SigninScreenHandler::HandleToggleEnrollmentScreen,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback("launchHelpApp",
       base::Bind(&SigninScreenHandler::HandleLaunchHelpApp,
                  base::Unretained(this)));
   web_ui()->RegisterMessageCallback("createAccount",
@@ skipping 294 matching lines @@
 
 void SigninScreenHandler::HandleShutdownSystem(const base::ListValue* args) {
 #if defined(USE_AURA)
   // Display the shutdown animation before actually requesting shutdown.
   ash::Shell::GetInstance()->power_button_controller()->RequestShutdown();
 #else
   DBusThreadManager::Get()->GetPowerManagerClient()->RequestShutdown();
 #endif
 }
 
+void SigninScreenHandler::HandleUserSelected(const base::ListValue* args) {
+  if (!delegate_)

[James Hawkins, 2012/04/26 20:37:37]

When would |delegate_| be NULL?

[Nikita (slow), 2012/04/27 12:00:49]

See http://codereview.chromium.org/10213003/

[James Hawkins, 2012/04/27 17:14:18]

OK, then these circumstances need to be documented.

[bshe, 2012/04/27 18:07:21]

It seems there are a few places in this file use this check and one of them
(http://code.google.com/searchframe#OAMlx_jo-ck/src/chrome/browser/ui/webui/ch...)
has comment about when this delegate_ is null. But I am not entirely sure if
this is the same situation since I am not familiar with the code.
+nikita could you please take a look? 
On 2012/04/27 17:14:18, James Hawkins wrote:

+    return;
+
+  std::string email;
+  if (!args->GetString(0, &email)) {
+    NOTREACHED();
+    return;
+  }
+
+  delegate_->UserSelected(email);
+}
+
 void SigninScreenHandler::HandleRemoveUser(const base::ListValue* args) {
   if (!delegate_)
     return;
 
   std::string email;
   if (!args->GetString(0, &email)) {
     NOTREACHED();
     return;
   }
 
@@ skipping 242 matching lines @@
       !dns_clear_task_running_ &&
       network_state_informer_->is_online()) {
     gaia_silent_load_ = true;
     gaia_silent_load_network_ =
         network_state_informer_->active_network_service_path();
     LoadAuthExtension(true, true, false);
   }
 }
 
 }  // namespace chromeos