Auto merge of #14623 - DominoTree:master, r=emilio

<!-- Please describe your changes on the following line: -->
Add check for bad ports to http_fetch(), return NetworkError::Internal if bad port/schema combination is seen.

Test added

---
<!-- 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 #14514 (github issue number if applicable).

<!-- Either: -->
- [x] There are tests for these changes OR

<!-- 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/14623)
<!-- Reviewable:end -->

tests/unit/net/fetch.rs

@@ -23,6 +23,7 @@ use hyper::status::StatusCode;
 use hyper::uri::RequestUri;
 use msg::constellation_msg::TEST_PIPELINE_ID;
 use net::fetch::cors_cache::CorsCache;
+use net_traits::NetworkError;
 use net_traits::ReferrerPolicy;
 use net_traits::request::{Origin, RedirectMode, Referrer, Request, RequestMode};
 use net_traits::response::{CacheState, Response, ResponseBody, ResponseType};
@@ -59,6 +60,18 @@ fn test_fetch_response_is_not_network_error() {
     }
 }
 
+#[test]
+fn test_fetch_on_bad_port_is_network_error() {
+    let url = ServoUrl::parse("http://www.example.org:6667").unwrap();
+    let origin = Origin::Origin(url.origin());
+    let request = Request::new(url, Some(origin), false, None);
+    *request.referrer.borrow_mut() = Referrer::NoReferrer;
+    let fetch_response = fetch(request, None);
+    assert!(fetch_response.is_network_error());
+    let fetch_error = fetch_response.get_network_error().unwrap();
+    assert!(fetch_error == &NetworkError::Internal("Request attempted on bad port".into()))
+}
+
 #[test]
 fn test_fetch_response_body_matches_const_message() {
     static MESSAGE: &'static [u8] = b"Hello World!";