Change more base::ListValue methods to use std::unique_ptr.

chrome/browser/chromeos/extensions/users_private/users_private_api.cc

Index: chrome/browser/chromeos/extensions/users_private/users_private_api.cc
diff --git a/chrome/browser/chromeos/extensions/users_private/users_private_api.cc b/chrome/browser/chromeos/extensions/users_private/users_private_api.cc
index 807498cebdef615a097fed624dd1aea3d3e687e7..467cf809e6d650b086a0bbf387e5a610d72ab2e2 100644
--- a/chrome/browser/chromeos/extensions/users_private/users_private_api.cc
+++ b/chrome/browser/chromeos/extensions/users_private/users_private_api.cc
@@ -84,9 +84,10 @@ UsersPrivateGetWhitelistedUsersFunction::Run() {
 
   user_manager::UserManager* user_manager = user_manager::UserManager::Get();
   const user_manager::UserList& users = user_manager->GetUsers();
-  for (user_manager::UserList::const_iterator it = users.begin();
-       it < users.end(); ++it)
-    email_list->AppendIfNotPresent(new base::StringValue((*it)->email()));
+  for (const auto* user : users) {
+    email_list->AppendIfNotPresent(
+        base::MakeUnique<base::StringValue>(user->email()));
+  }
 
   if (chromeos::OwnerSettingsServiceChromeOS* service =
           chromeos::OwnerSettingsServiceChromeOSFactory::GetForBrowserContext(