Auto merge of #19547 - tigercosmos:b1, r=jdm

Send IPC receiver for canvas as part of CreateCanvasPaintThread message

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I am not sure if @jdm want this.
r? @jdm

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #19483(github issue number if applicable).

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- [ ] These changes do not require tests because _____

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components/script/dom/canvasrenderingcontext2d.rs

@@ -129,11 +129,10 @@ impl CanvasRenderingContext2D {
                          size: Size2D<i32>)
                          -> CanvasRenderingContext2D {
         debug!("Creating new canvas rendering context.");
-        let (sender, receiver) = ipc::channel().unwrap();
+        let (ipc_renderer, receiver) = ipc::channel::<CanvasMsg>().unwrap();
         let script_to_constellation_chan = global.script_to_constellation_chan();
         debug!("Asking constellation to create new canvas thread.");
-        script_to_constellation_chan.send(ScriptMsg::CreateCanvasPaintThread(size, sender)).unwrap();
-        let ipc_renderer = receiver.recv().unwrap();
+        script_to_constellation_chan.send(ScriptMsg::CreateCanvasPaintThread(size, receiver)).unwrap();
         debug!("Done.");
         CanvasRenderingContext2D {
             reflector_: Reflector::new(),