Android: Keyboard doesn't hide from done button

TextInput does hide and commit remove it from TextField.

Task-number: QTBUG-37850
Change-Id: I6a77f856ece4856e7f745ab4a75b214997abf7d8
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@theqtcompany.com>