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

Properly set origin of fetch requests

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These changes aim to fix #15247

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

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- [ ] 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).

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components/net_traits/request.rs

@@ -158,9 +158,7 @@ pub struct RequestInit {
     pub use_cors_preflight: bool,
     pub credentials_mode: CredentialsMode,
     pub use_url_credentials: bool,
-    // this should actually be set by fetch, but fetch
-    // doesn't have info about the client right now
-    pub origin: ServoUrl,
+    pub origin: ImmutableOrigin,
     // XXXManishearth these should be part of the client object
     pub referrer_url: Option<ServoUrl>,
     pub referrer_policy: Option<ReferrerPolicy>,
@@ -188,7 +186,7 @@ impl Default for RequestInit {
             use_cors_preflight: false,
             credentials_mode: CredentialsMode::Omit,
             use_url_credentials: false,
-            origin: ServoUrl::parse("about:blank").unwrap(),
+            origin: ImmutableOrigin::new_opaque(),
             referrer_url: None,
             referrer_policy: None,
             pipeline_id: None,
@@ -302,7 +300,7 @@ impl Request {
 
     pub fn from_init(init: RequestInit) -> Request {
         let mut req = Request::new(init.url.clone(),
-                                   Some(Origin::Origin(init.origin.origin())),
+                                   Some(Origin::Origin(init.origin)),
                                    init.pipeline_id);
         req.method = init.method;
         req.headers = init.headers;