bug(web): inconsistency firing `keyboardchange` events

With #16080 fixed, the Control-by-Control guide example now reveals an inconsistency when firing `keyboardchange` events:

If the text field was active and we then click in the subject field (with the system keyboard being active), a `keyboardchange` event gets fired.

However, if the address field was active and we click in the subject field (with the system keyboard being active), the `keyboardchange` event is NOT fired. If a Keyman keyboard is active then the event fires.