Auto merge of #23499 - est31:unused_code_removal_3, r=jdm

Remove unused code (3/N)

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Third PR in a series of PRs to remove unused/dead code from servo, powered by an (upcoming) tool of mine. Please take a look and tell me if you want to keep something.

* First PR: #23477
* Second PR: #23498

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #___ (GitHub issue number if applicable)

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because they only remove dead code

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components/canvas/canvas_data.rs

@@ -1146,26 +1146,6 @@ fn write_image(
     draw_target.draw_surface(source_surface, dest_rect, image_rect, filter, draw_options);
 }
 
-pub trait PointToi32 {
-    fn to_i32(&self) -> Point2D<i32>;
-}
-
-impl PointToi32 for Point2D<f64> {
-    fn to_i32(&self) -> Point2D<i32> {
-        Point2D::new(self.x.to_i32().unwrap(), self.y.to_i32().unwrap())
-    }
-}
-
-pub trait SizeToi32 {
-    fn to_i32(&self) -> Size2D<i32>;
-}
-
-impl SizeToi32 for Size2D<f64> {
-    fn to_i32(&self) -> Size2D<i32> {
-        Size2D::new(self.width.to_i32().unwrap(), self.height.to_i32().unwrap())
-    }
-}
-
 pub trait RectToi32 {
     fn to_i32(&self) -> Rect<i32>;
     fn ceil(&self) -> Rect<f64>;