Sets whether or not @self will interpolate the size of its opposing
orientation when changing the visible child. If %TRUE, @self will interpolate
its size between the one of the previous visible child and the one of the new
visible child, according to the set transition duration and the orientation,
e.g. if @self is horizontal, it will interpolate the its height.
Sets whether or not @self will interpolate the size of its opposing orientation when changing the visible child. If %TRUE, @self will interpolate its size between the one of the previous visible child and the one of the new visible child, according to the set transition duration and the orientation, e.g. if @self is horizontal, it will interpolate the its height.