Merge unnecessary split widget modules

graphics/src/widget/space.rs

@@ -0,0 +1,15 @@
+use crate::{Backend, Primitive, Renderer};
+use iced_native::mouse;
+use iced_native::space;
+use iced_native::Rectangle;
+
+pub use iced_native::Space;
+
+impl<B> space::Renderer for Renderer<B>
+where
+    B: Backend,
+{
+    fn draw(&mut self, _bounds: Rectangle) -> Self::Output {
+        (Primitive::None, mouse::Interaction::default())
+    }
+}