[orca-list] Shift and shift plus tab not working, Google Chrome dev Orca master latest commit

[Pavel Vlček <vlcekpavel93 gmail com>]

Steps to reproduce:

- check if you have the latest Chromium / Google Chrome dev version and 
the latest Orca Master version

- open Chromium / Chrome

- go to www.google.com

expected result:

- Orca will navigate with tab and shift tab between links and form elements

actual result:

- Navigation with tab and shift tab not working.

My system Fedora 31, the latest Google Chrome and the latest Orca 
Master, navigation worked before I updated to the latest commit.

Pavel