How to reproduce:
1. Open the attached "InputActionMapStackBug.zip" project
2. Open the "SampleScene" Scene
3. Connect Xbox One controller -> Enter the Play Mode
4. Press A (submit) on an Xbox One controller -> Press B (cancel)
5. Observe Console Window

Expected result: No errors appear
Actual result: "IndexOutOfRangeException while executing 'performed' callbacks" error appears

Reproducible with: 2019.4.8f1, 2020.1.2f1, 2020.2.0a20 (1.0.0)

Full error:
IndexOutOfRangeException while executing 'performed' callbacks of 'UI/Cancel[/Keyboard/escape,/XInputControllerWindows/buttonEast]'
UnityEngine.InputSystem.LowLevel.NativeInputRuntime/<>c__DisplayClass7_0:<set_onUpdate>b__0 (UnityEngineInternal.Input.NativeInputUpdateType,UnityEngineInternal.Input.NativeInputEventBuffer*)
UnityEngineInternal.Input.NativeInputSystem:NotifyUpdate (UnityEngineInternal.Input.NativeInputUpdateType,intptr)

Notes:
- Could not test on 2018.4, because input System Package is not available in that stream
- Could not on versions lower than 1.0.0, because of Scripting errors