Stop creating image pipeline when unnecessary

wgpu/src/texture/atlas/layer.rs

@@ -1,17 +0,0 @@
-use crate::texture::atlas::Allocator;
-
-#[derive(Debug)]
-pub enum Layer {
-    Empty,
-    Busy(Allocator),
-    Full,
-}
-
-impl Layer {
-    pub fn is_empty(&self) -> bool {
-        match self {
-            Layer::Empty => true,
-            _ => false,
-        }
-    }
-}