Allow recommended locales to be set for public sessions

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 1a81b41d14ffce525b2a9a2a2ff988c102b16417..15187a46410a49760a25c6ac5263650ca4852a8e 100644
--- a/chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc
+++ b/chrome/browser/chromeos/login/screens/chrome_user_selection_screen.cc
@@ -6,15 +6,24 @@
 
 #include "base/bind.h"
 #include "base/location.h"
+#include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/values.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_process_platform_part.h"
 #include "chrome/browser/chromeos/login/users/user_manager.h"
 #include "chrome/browser/chromeos/policy/browser_policy_connector_chromeos.h"
+#include "chrome/browser/ui/webui/chromeos/login/l10n_util.h"
 #include "chrome/browser/ui/webui/chromeos/login/signin_screen_handler.h"
+#include "components/policy/core/common/cloud/cloud_policy_core.h"
+#include "components/policy/core/common/cloud/cloud_policy_store.h"
+#include "components/policy/core/common/policy_map.h"
+#include "components/policy/core/common/policy_types.h"
 #include "components/user_manager/user.h"
 #include "components/user_manager/user_type.h"
+#include "policy/policy_constants.h"
 
 namespace chromeos {
 
@@ -54,6 +63,7 @@ void ChromeUserSelectionScreen::OnPolicyUpdated(const std::string& user_id) {
     return;
 
   CheckForPublicSessionDisplayNameChange(broker);
+  CheckForPublicSessionLocalePolicyChange(broker);
 }
 
 void ChromeUserSelectionScreen::OnDeviceLocalAccountsChanged() {
@@ -91,6 +101,55 @@ void ChromeUserSelectionScreen::CheckForPublicSessionDisplayNameChange(
                  user_id));
 }
 
+void ChromeUserSelectionScreen::CheckForPublicSessionLocalePolicyChange(
+    policy::DeviceLocalAccountPolicyBroker* broker) {
+  const std::string& user_id = broker->user_id();
+  const policy::PolicyMap::Entry* entry =
+      broker->core()->store()->policy_map().Get(policy::key::kSessionLocales);
+
+  // Parse the list of recommended locales set by policy.
+  std::vector<std::string> new_recommended_locales;
+  base::ListValue const* list = NULL;
+  if (entry &&
+      entry->level == policy::POLICY_LEVEL_RECOMMENDED &&
+      entry->value &&
+      entry->value->GetAsList(&list)) {
+    for (base::ListValue::const_iterator it = list->begin(); it != list->end();
+         ++it) {
+      std::string locale;
+      if (!(*it)->GetAsString(&locale)) {
+        NOTREACHED();
+        new_recommended_locales.clear();
+        break;
+      }
+      new_recommended_locales.push_back(locale);
+    }
+  }
+
+  if (new_recommended_locales.empty()) {
+    // There are no recommended locales.
+    PublicSessionRecommendedLocaleMap::iterator it =
+        public_session_recommended_locales_.find(user_id);
+    if (it != public_session_recommended_locales_.end()) {
+      // If there previously were recommended locales, remove them from
+      // |public_session_recommended_locales_| and notify the UI.
+      public_session_recommended_locales_.erase(it);
+      SetPublicSessionLocales(user_id, &new_recommended_locales);
+    }
+    return;
+  }
+
+  // There are recommended locales.
+  std::vector<std::string>& recommended_locales =
+      public_session_recommended_locales_[user_id];
+  if (new_recommended_locales != recommended_locales) {
+    // If the list of recommended locales has changed, update
+    // |public_session_recommended_locales_| and notify the UI.
+    recommended_locales = new_recommended_locales;
+    SetPublicSessionLocales(user_id, &new_recommended_locales);
+  }
+}
+
 void ChromeUserSelectionScreen::SetPublicSessionDisplayName(
     const std::string& user_id) {
   const user_manager::User* user = UserManager::Get()->FindUser(user_id);
@@ -102,4 +161,33 @@ void ChromeUserSelectionScreen::SetPublicSessionDisplayName(
       base::UTF16ToUTF8(user->GetDisplayName()));
 }
 
+void ChromeUserSelectionScreen::SetPublicSessionLocales(
+    const std::string& user_id,
+    const std::vector<std::string>* recommended_locales) {
+  if (!handler_initialized_)
+    return;
+
+  // Construct the list of available locales. This list consists of the
+  // recommended locales, followed by all others.
+  scoped_ptr<base::ListValue> 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 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
+  // expands to its basic form (for zero or one recommended locales) or the
+  // advanced form (two or more recommended locales).
+  const bool two_or_more_recommended_locales = recommended_locales->size() >= 2;
+
+  // Notify the UI.
+  handler_->SetPublicSessionLocales(user_id,
+                                    locales.Pass(),
+                                    default_locale,
+                                    two_or_more_recommended_locales);
+}
+
 }  // namespace chromeos