Asynchronously load wallpapers when user pod is selected.

chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc

Index: chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
diff --git a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
index 106521af27755abdf39b2c5aaf1ecbdfe238e47c..132ca67209c35a078bfe705374dd9e62f57108f8 100644
--- a/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
+++ b/chrome/browser/ui/webui/chromeos/login/signin_screen_handler.cc
@@ -440,6 +440,9 @@ void SigninScreenHandler::RegisterMessages() {
   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)));
@@ -754,6 +757,19 @@ void SigninScreenHandler::HandleShutdownSystem(const base::ListValue* args) {
 #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;