Auto merge of #21187 - tigercosmos:fetch, r=jdm

Make fetch() API use same-origin credentials by default

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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 #21146 (github issue number if applicable).

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- [ ] There are tests for these changes OR
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components/script/dom/request.rs

@@ -106,7 +106,7 @@ impl Request {
                 // Step 5.5
                 fallback_mode = Some(NetTraitsRequestMode::CorsMode);
                 // Step 5.6
-                fallback_credentials = Some(NetTraitsRequestCredentials::Omit);
+                fallback_credentials = Some(NetTraitsRequestCredentials::CredentialsSameOrigin);
             }
             // Step 6
             RequestInfo::Request(ref input_request) => {

tests/wpt/metadata/fetch/api/request/request-init-003.sub.html.ini

@@ -1,4 +0,0 @@
-[request-init-003.sub.html]
-  [Check request values when initialized from url string]
-    expected: FAIL
-

tests/wpt/metadata/fetch/api/request/request-structure.html.ini

@@ -1,7 +1,4 @@
 [request-structure.html]
-  [Check credentials attribute]
-    expected: FAIL
-
   [Check isReloadNavigation attribute]
     expected: FAIL