originally filed by @zadjii-msft

I guess this is a toggle between:

• Fully dismiss
• Dismiss search text if there is any, otherwise go back

(because an always-go-back didn't seem valuable)

I think we wanted to have three states for Escape:

1. The current behavior: dismiss search if there isn't one, otherwise go back
2. Go back always
3. Dismiss always (go home & hide)