Place sign out button on ash tray bubble in lockscreen state.

ash/system/user/tray_user.cc

Index: ash/system/user/tray_user.cc
diff --git a/ash/system/user/tray_user.cc b/ash/system/user/tray_user.cc
index 94a85ea07a55b7705989b9ca44110e4d070dc461..42bb55a8d2be08d76d83c47cfca60cf82c37a30c 100644
--- a/ash/system/user/tray_user.cc
+++ b/ash/system/user/tray_user.cc
@@ -761,11 +761,6 @@ void UserView::ButtonPressed(views::Button* sender, const ui::Event& event) {
 }
 
 void UserView::AddLogoutButton(ash::user::LoginStatus login) {
-  // A user should not be able to modify logged-in state when screen is
-  // locked.
-  if (login == ash::user::LOGGED_IN_LOCKED)
-    return;
-
   const base::string16 title = ash::user::GetLocalizedSignOutStringForStatus(
       login, true);
   TrayPopupLabelButton* logout_button = new TrayPopupLabelButton(this, title);