Auto merge of #18242 - joone:ellipse, r=jdm

Implement Ellipse Canvas 2D API

This patch needs to update rust-azure to 0.21.0.

- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #17598

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components/canvas/canvas_paint_thread.rs

@@ -173,6 +173,9 @@ impl<'a> CanvasPaintThread<'a> {
                             Canvas2dMsg::ArcTo(ref cp1, ref cp2, radius) => {
                                 painter.arc_to(cp1, cp2, radius)
                             }
+                            Canvas2dMsg::Ellipse(ref center, radius_x, radius_y, rotation, start, end, ccw) => {
+                                painter.ellipse(center, radius_x, radius_y, rotation, start, end, ccw)
+                            }
                             Canvas2dMsg::RestoreContext => painter.restore_context_state(),
                             Canvas2dMsg::SaveContext => painter.save_context_state(),
                             Canvas2dMsg::SetFillStyle(style) => painter.set_fill_style(style),
@@ -501,6 +504,17 @@ impl<'a> CanvasPaintThread<'a> {
         }
     }
 
+    fn ellipse(&mut self,
+           center: &Point2D<AzFloat>,
+           radius_x: AzFloat,
+           radius_y: AzFloat,
+           rotation_angle: AzFloat,
+           start_angle: AzFloat,
+           end_angle: AzFloat,
+           ccw: bool) {
+        self.path_builder.ellipse(*center, radius_x, radius_y, rotation_angle, start_angle, end_angle, ccw);
+    }
+
     fn set_fill_style(&mut self, style: FillOrStrokeStyle) {
         if let Some(pattern) = style.to_azure_pattern(&self.drawtarget) {
             self.state.fill_style = pattern