message: Make `Element::hash_layout` public.
diff: @@ -242,7 +242,10 @@ where
  .draw(renderer, defaults, layout, cursor_position)
  }
  - pub(crate) fn hash_layout(&self, state: &mut Hasher) {
  + /// Computes the _layout_ hash of the [`Element`].
  + ///
  + /// [`Element`]: struct.Element.html
  + pub fn hash_layout(&self, state: &mut Hasher) {
  self.widget.hash_layout(state);
  }
  }
  