arc: Start ARC for Public Session users.

components/arc/arc_util.cc

Index: components/arc/arc_util.cc
diff --git a/components/arc/arc_util.cc b/components/arc/arc_util.cc
index 83436fe2d1ed0d612ebe28c4d12a918736550c68..986807fb5022f3976b8429fd77daa8ae926fd878 100644
--- a/components/arc/arc_util.cc
+++ b/components/arc/arc_util.cc
@@ -145,6 +145,11 @@ bool IsArcKioskMode() {
          user_manager::UserManager::Get()->IsLoggedInAsArcKioskApp();
 }
 
+bool IsPublicSessionMode() {
+  return user_manager::UserManager::IsInitialized() &&
+         user_manager::UserManager::Get()->IsLoggedInAsPublicAccount();
+}
+
 bool IsArcAllowedForUser(const user_manager::User* user) {
   if (!user) {
     VLOG(1) << "No ARC for nullptr user.";
@@ -155,23 +160,18 @@ bool IsArcAllowedForUser(const user_manager::User* user) {
   // - Users have Gaia accounts;
   // - Active directory users;
   // - ARC kiosk session;
+  // - Public Session users;
   //   USER_TYPE_ARC_KIOSK_APP check is compatible with IsArcKioskMode()
   //   above because ARC kiosk user is always the primary/active user of a
-  //   user session.
+  //   user session. The same for USER_TYPE_PUBLIC_ACCOUNT.
   if (!user->HasGaiaAccount() && !user->IsActiveDirectoryUser() &&
-      user->GetType() != user_manager::USER_TYPE_ARC_KIOSK_APP) {
+      user->GetType() != user_manager::USER_TYPE_ARC_KIOSK_APP &&
+      user->GetType() != user_manager::USER_TYPE_PUBLIC_ACCOUNT) {
     VLOG(1) << "Users without GAIA or AD accounts, or not ARC kiosk apps are "
                "not supported in ARC.";
     return false;
   }
 
-  // Do not allow for ephemeral data user. cf) b/26402681
-  if (user_manager::UserManager::Get()->IsUserCryptohomeDataEphemeral(
-          user->GetAccountId())) {
-    VLOG(1) << "Users with ephemeral data are not supported in ARC.";
-    return false;
-  }
-
   return true;
 }