Version: dev-master

Bug Description

The callable definitions introduced in #216 fail to support custom mapped types:

class MappedValues { public string $name; } $form = new Nette\Forms\Form(); $form–>addText('name', 'Name'); $form->setMappedType(MappedValues::class); $form->onSuccess[] = function (Form $form, MappedValues $values) {};

produces

Array (array<(callable(Nette\Forms\Form, array): void)|(callable(Nette\Forms\Form, Nette\Utils\ArrayHash): void)>) does not accept Closure(Nette\Forms\Form, MappedValues): void. 

I don't know how the variance works there, but neither adding callable(Form, object) nor class MappedValues extends ArrayHash seemed to help. Perhaps @ondrejmirtes or @JanTvrdik could chime in please?