Default to current UI locale when recommended locales are invalid

chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc

Index: chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc
diff --git a/chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc b/chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc
index 4eecbd97ca22f54944e4b5c9eb7ba08dbcd64749..ac58a0d9e71e1e38bd6a1673c29698ebf50110db 100644
--- a/chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc
+++ b/chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc
@@ -170,13 +170,15 @@ void ChromeUserSelectionScreen::SetPublicSessionLocales(
 
   // Construct the list of available locales. This list consists of the
   // recommended locales, followed by all others.
-  scoped_ptr<base::ListValue> locales =
+  scoped_ptr<base::ListValue> available_locales =
       GetUILanguageList(recommended_locales, std::string());
 
-  // Set the initially selected locale. If the list of recommended locales is
-  // not empty, select its first entry. Otherwise, select the current UI locale.
-  const std::string& default_locale = recommended_locales->empty() ?
-      g_browser_process->GetApplicationLocale() : recommended_locales->front();
+  // Set the initially selected locale to the first recommended locale that is
+  // actually available or the current UI locale if none of them are available.
+  const std::string default_locale = FindMostRelevantLocale(
+      recommended_locales,
+      *available_locales.get(),
+      g_browser_process->GetApplicationLocale());
 
   // Set a flag to indicate whether the list of recommended locales contains at
   // least two entries. This is used to decide whether the public session pod
@@ -186,7 +188,7 @@ void ChromeUserSelectionScreen::SetPublicSessionLocales(
 
   // Notify the UI.
   handler_->SetPublicSessionLocales(user_id,
-                                    locales.Pass(),
+                                    available_locales.Pass(),
                                     default_locale,
                                     two_or_more_recommended_locales);
 }