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

Send IPC receiver for canvas as part of CreateCanvasPaintThread message

<!-- Please describe your changes on the following line: -->
I am not sure if @jdm want this.
r? @jdm

---
<!-- 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
- [X] These changes fix #19483(github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/19547)
<!-- Reviewable:end -->

components/script_traits/script_msg.rs

@@ -79,7 +79,7 @@ pub enum ScriptMsg {
     ChangeRunningAnimationsState(AnimationState),
     /// Requests that a new 2D canvas thread be created. (This is done in the constellation because
     /// 2D canvases may use the GPU and we don't want to give untrusted content access to the GPU.)
-    CreateCanvasPaintThread(Size2D<i32>, IpcSender<IpcSender<CanvasMsg>>),
+    CreateCanvasPaintThread(Size2D<i32>, IpcReceiver<CanvasMsg>),
     /// Notifies the constellation that this frame has received focus.
     Focus,
     /// Forward an event that was sent to the parent window.