parameter 'widget' of BoundField.as_widget is ignored

[Sven R. Kunze]

'as_widget' has the parameter 'widget' which renders the field. However, this parameter is not used all the time during the 'as_widget' call.

The method 'data', which is (indirectly via 'value') called by 'as_widget' ALWAYS used the default widget of the field which leads to issues like formatting etc.

We recognized this issue when using 'show_hidden_initial=True' and widgets for datetime objects.

The problem can also be observed when using BoundField.as_hidden as it uses 'as_widget' as well.

cf.
as_widget: ​https://github.com/django/django/blob/master/django/forms/forms.py#L526
data: ​https://github.com/django/django/blob/master/django/forms/forms.py#L569
as_hidden: ​https://github.com/django/django/blob/master/django/forms/forms.py#L562