[cros login] Always show public sessions even when user pods are not …

…shown per policy.

BUG=363983
TEST=Manually: enrolled to domain with public session configured, disabled user pods on login screen per policy.

Review URL: https://codereview.chromium.org/264453007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@267347 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/chromeos/login/existing_user_controller.cc

@@ -188,31 +188,35 @@ void ExistingUserController::UpdateLoginDisplay(const UserList& users) {
 
   cros_settings_->GetBoolean(kAccountsPrefShowUserNamesOnSignIn,
                              &show_users_on_signin);
-  if (show_users_on_signin) {
-    for (UserList::const_iterator it = users.begin(); it != users.end(); ++it) {
-      // TODO(xiyuan): Clean user profile whose email is not in whitelist.
-      bool meets_locally_managed_requirements =
-          (*it)->GetType() != User::USER_TYPE_LOCALLY_MANAGED ||
-          UserManager::Get()->AreLocallyManagedUsersAllowed();
-      bool meets_whitelist_requirements =
-          LoginUtils::IsWhitelisted((*it)->email(), NULL) ||
-          (*it)->GetType() != User::USER_TYPE_REGULAR;
-      if (meets_locally_managed_requirements && meets_whitelist_requirements) {
-        filtered_users.push_back(*it);
-      }
+  for (UserList::const_iterator it = users.begin(); it != users.end(); ++it) {
+    // TODO(xiyuan): Clean user profile whose email is not in whitelist.
+    bool meets_locally_managed_requirements =
+        (*it)->GetType() != User::USER_TYPE_LOCALLY_MANAGED ||
+        UserManager::Get()->AreLocallyManagedUsersAllowed();
+    bool meets_whitelist_requirements =
+        LoginUtils::IsWhitelisted((*it)->email(), NULL) ||
+        (*it)->GetType() != User::USER_TYPE_REGULAR;
+
+    // Public session accounts are always shown on login screen.
+    bool meets_show_users_requirements = show_users_on_signin ||
+        (*it)->GetType() == User::USER_TYPE_PUBLIC_ACCOUNT;
+    if (meets_locally_managed_requirements &&
+        meets_whitelist_requirements &&
+        meets_show_users_requirements) {
+      filtered_users.push_back(*it);
     }
   }
 
   // If no user pods are visible, fallback to single new user pod which will
   // have guest session link.
   bool show_guest;
   cros_settings_->GetBoolean(kAccountsPrefAllowGuest, &show_guest);
-  bool show_users;
-  cros_settings_->GetBoolean(kAccountsPrefShowUserNamesOnSignIn, &show_users);
+  show_users_on_signin |= !filtered_users.empty();
   show_guest &= !filtered_users.empty();
   bool show_new_user = true;
   login_display_->set_parent_window(GetNativeWindow());
-  login_display_->Init(filtered_users, show_guest, show_users, show_new_user);
+  login_display_->Init(
+      filtered_users, show_guest, show_users_on_signin, show_new_user);
   host_->OnPreferencesChanged();
 }
 

chrome/browser/chromeos/login/wallpaper_manager.cc

@@ -203,6 +203,22 @@ bool SaveWallpaperInternal(const base::FilePath& path,
   return written_bytes == size;
 }
 
+// Returns index of the first public session user found in |users|
+// or -1 otherwise.
+int FindPublicSession(const chromeos::UserList& users) {
+  int index = -1;
+  int i = 0;
+  for (UserList::const_iterator it = users.begin();
+       it != users.end(); ++it, ++i) {
+    if ((*it)->GetType() == User::USER_TYPE_PUBLIC_ACCOUNT) {
+      index = i;
+      break;
+    }
+  }
+
+  return index;
+}
+
 }  // namespace
 
 const char kWallpaperSequenceTokenName[] = "wallpaper-sequence";
@@ -1295,17 +1311,19 @@ void WallpaperManager::InitializeRegisteredDeviceWallpaper() {
   DCHECK(result) << "Unable to fetch setting "
                  << kAccountsPrefShowUserNamesOnSignIn;
   const chromeos::UserList& users = UserManager::Get()->GetUsers();
-  if (!show_users || users.empty()) {
+  int public_session_user_index = FindPublicSession(users);
+  if ((!show_users && public_session_user_index == -1) || users.empty()) {
     // Boot into sign in form, preload default wallpaper.
     SetDefaultWallpaperDelayed(UserManager::kSignInUser);
     return;
   }
 
   if (!disable_boot_animation) {
+    int index = public_session_user_index != -1 ? public_session_user_index : 0;
     // Normal boot, load user wallpaper.
     // If normal boot animation is disabled wallpaper would be set
     // asynchronously once user pods are loaded.
-    SetUserWallpaperDelayed(users[0]->email());
+    SetUserWallpaperDelayed(users[index]->email());
   }
 }
 

chrome/browser/chromeos/login/webui_login_display.h

@@ -109,7 +109,8 @@ class WebUILoginDisplay : public LoginDisplay,
   // Whether to show guest login.
   bool show_guest_;
 
-  // Weather to show the user pads or a plain credentials dialogue.
+  // Weather to show the user pods or a GAIA sign in.
+  // Public sessions are always shown.
   bool show_users_;
 
   // Whether to show add new user.

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

@@ -171,7 +171,8 @@ class SigninScreenHandlerDelegate {
   // Whether login as guest is available.
   virtual bool IsShowGuest() const = 0;
 
-  // Whether login as guest is available.
+  // Weather to show the user pods or only GAIA sign in.
+  // Public sessions are always shown.
   virtual bool IsShowUsers() const = 0;
 
   // Whether new user pod is available.