Auto merge of #16508 - brainlessdeveloper:fetch-set-origin, r=asajeffrey

Properly set origin of fetch requests

<!-- Please describe your changes on the following line: -->

These changes aim to fix #15247

---
<!-- 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 #15247 (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes
- [x] These changes do not require tests because cors is already tested with different origins

These changes require changes in tests, but I need help with that (see comments below).

<!-- 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/16508)
<!-- Reviewable:end -->

components/net/http_loader.rs

@@ -1371,7 +1371,7 @@ fn cors_check(request: &Request, response: &Response) -> Result<(), ()> {
     };
 
     match request.origin {
-        Origin::Origin(ref o) if o.ascii_serialization() == origin => {},
+        Origin::Origin(ref o) if o.ascii_serialization() == origin.trim() => {},
         _ => return Err(())
     }