Remove canvas::Data leftover

wgpu/src/widget/canvas/data.rs

@@ -1,20 +0,0 @@
-#[derive(Debug, Clone, Copy, Default, PartialEq, Eq)]
-pub struct Data<T> {
-    raw: T,
-    version: usize,
-}
-
-impl<T> Data<T> {
-    pub fn new(data: T) -> Self {
-        Data {
-            raw: data,
-            version: 0,
-        }
-    }
-
-    pub fn update(&mut self, f: impl FnOnce(&mut T)) {
-        f(&mut self.raw);
-
-        self.version += 1;
-    }
-}