Auto merge of #13561 - mathieuh:request-constructor, r=<try>

Make Request throw less often (fixes #13457)

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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 #13457

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components/script/dom/request.rs

@@ -181,9 +181,8 @@ impl Request {
             !init.window.is_undefined() {
                 // Step 13.1
                 if request.mode == NetTraitsRequestMode::Navigate {
-                    return Err(Error::Type(
-                        "Init is present and request mode is 'navigate'".to_string()));
-                    }
+                    request.mode = NetTraitsRequestMode::SameOrigin;
+                }
                 // Step 13.2
                 request.omit_origin_header.set(false);
                 // Step 13.3
@@ -211,15 +210,11 @@ impl Request {
                 if let Ok(parsed_referrer) = parsed_referrer {
                     if parsed_referrer.cannot_be_a_base() &&
                         parsed_referrer.scheme() == "about" &&
-                        parsed_referrer.path() == "client" {
+                        parsed_referrer.path() == "client" ||
+                        parsed_referrer.origin() != origin {
                             *request.referrer.borrow_mut() = NetTraitsRequestReferrer::Client;
                         } else {
                             // Step 14.6
-                            if parsed_referrer.origin() != origin {
-                                return Err(Error::Type(
-                                    "RequestInit's referrer has invalid origin".to_string()));
-                            }
-                            // Step 14.7
                             *request.referrer.borrow_mut() = NetTraitsRequestReferrer::ReferrerUrl(parsed_referrer);
                         }
                 }