Determining the enabled state of a widget from whether its Clicked method has
been called only works for button-like widgets. For example, it's not clear a
Clicked method is appropriate for a CheckBox.
Remove the feature for now, and let's find a better design in the future.
As a nice side effect, we can now process events in Layout methods, so that
buttons react to user input even when Clicked is not called.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Elias Naur