InputActionMap.AddAction cannot resolve

Unity Engine
1

I’m trying to add actions in code to an InputActionMap. For some reason the AddAction() method isn’t available. This is U201910f2 and NIS 1.0.0.

 UnityEngine.InputSystem.InputActionMap actionMap = uisPlayerInput.actions.FindActionMap(uisPlayerInput.defaultActionMap);

UnityEngine.InputSystem.InputAction action = actionMap.FindAction("Horizontal");
 if (action == null)
{
   var horizontalAction = new UnityEngine.InputSystem.InputAction("Horizontal", binding: "<Gamepad>/leftStick");

   actionMap.AddAction(...) ??? // AddAction method not available...

}
2

Seems to have moved to UnityEngine.InputSystem.InputActionSetupExtensions.AddAction(…)