Auto merge of #23135 - maharsh312:master, r=jdm

Create CanvasRect for OffscreenCanvas

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Created CanvasRect fot OffscreenCanvas and Updated Testcases

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components/constellation/constellation.rs

@@ -3108,7 +3108,7 @@ where
 
     fn handle_create_canvas_paint_thread_msg(
         &mut self,
-        size: Size2D<u32>,
+        size: Size2D<u64>,
         response_sender: IpcSender<(IpcSender<CanvasMsg>, CanvasId)>,
     ) {
         let webrender_api = self.webrender_api_sender.clone();