Create Mojo Struct for user information used in login/lock screen.

chrome/browser/chromeos/login/lock/views_screen_locker.cc

Index: chrome/browser/chromeos/login/lock/views_screen_locker.cc
diff --git a/chrome/browser/chromeos/login/lock/views_screen_locker.cc b/chrome/browser/chromeos/login/lock/views_screen_locker.cc
index d68c66677ebc3b1f94bd71766cb7dc83d7685f90..9e74501548e16aa421b3a8b87712bfe489874d4d 100644
--- a/chrome/browser/chromeos/login/lock/views_screen_locker.cc
+++ b/chrome/browser/chromeos/login/lock/views_screen_locker.cc
@@ -52,8 +52,9 @@ ViewsScreenLocker::~ViewsScreenLocker() {
 void ViewsScreenLocker::Init() {
   lock_time_ = base::TimeTicks::Now();
   user_selection_screen_->Init(screen_locker_->users());
-  LockScreenClient::Get()->LoadUsers(user_selection_screen_->PrepareUserList(),
-                                     false /* show_guests */);
+  LockScreenClient::Get()->LoadUsers(
+      user_selection_screen_->UpdateAndReturnUserListForMojo(),
+      false /* show_guests */);
   if (!ime_state_.get())
     ime_state_ = input_method::InputMethodManager::Get()->GetActiveIMEState();