When calling any of:
- Widget::setEnabled
- EditTextWidget::setEditString
- EditableWidget::setEditString
- StaticTextWidget::setLabel
there is no need to call neither GuiManager::scheduleTopDialogRedraw nor
Widget::markAsDirty afterwards -- they set up the call by themselves.
Also, refactor a couple of code blocks into calling just
GuiManager::redrawFull as it does the same thing.