Auto merge of #24342 - petosorus:null_responseXml, r=jdm

XMLHttpRequest.responseXML returns null when a network error occurs

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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 #24285 (GitHub issue number if applicable)

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- [x] There are tests for these changes OR
- [ ] These changes do not require tests because tests ___

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components/script/dom/xmlhttprequest.rs

@@ -1292,12 +1292,17 @@ impl XMLHttpRequest {
 
     // https://xhr.spec.whatwg.org/#document-response
     fn document_response(&self) -> Option<DomRoot<Document>> {
-        // Step 1
+        // Caching: if we have existing response xml, redirect it directly
         let response = self.response_xml.get();
         if response.is_some() {
             return self.response_xml.get();
         }
 
+        // Step 1
+        if self.response_status.get().is_err() {
+            return None;
+        }
+
         let mime_type = self.final_mime_type();
         // TODO: prescan the response to determine encoding if final charset is null
         let charset = self.final_charset().unwrap_or(UTF_8);

tests/wpt/metadata/xhr/abort-after-send.any.js.ini

@@ -1,6 +0,0 @@
-[abort-after-send.any.html]
-  [XMLHttpRequest: abort() after send()]
-    expected: FAIL
-
-
-[abort-after-send.any.worker.html]

tests/wpt/metadata/xhr/send-redirect-to-cors.htm.ini

@@ -6,27 +6,6 @@
   [XMLHttpRequest: send() - Redirect to CORS-enabled resource (307 post with typed array)]
     expected: FAIL
 
-  [XMLHttpRequest: send() - Redirect to CORS-enabled resource (301 GET with explicit Content-Type)]
-    expected: FAIL
-
-  [XMLHttpRequest: send() - Redirect to CORS-enabled resource (301 POST with string and explicit Content-Type)]
-    expected: FAIL
-
-  [XMLHttpRequest: send() - Redirect to CORS-enabled resource (302 POST with string and explicit Content-Type)]
-    expected: FAIL
-
-  [XMLHttpRequest: send() - Redirect to CORS-enabled resource (307 POST with string and explicit Content-Type)]
-    expected: FAIL
-
-  [XMLHttpRequest: send() - Redirect to CORS-enabled resource (307 FOO with string and explicit Content-Type)]
-    expected: FAIL
-
-  [XMLHttpRequest: send() - Redirect to CORS-enabled resource (308 POST with string and explicit Content-Type)]
-    expected: FAIL
-
-  [XMLHttpRequest: send() - Redirect to CORS-enabled resource (308 FOO with string and explicit Content-Type)]
-    expected: FAIL
-
   [XMLHttpRequest: send() - Redirect to CORS-enabled resource (308 FOO with string and explicit Content-Type text/plain)]
     expected: FAIL
 

tests/wpt/metadata/xhr/xmlhttprequest-network-error-sync.htm.ini

@@ -1,5 +0,0 @@
-[xmlhttprequest-network-error-sync.htm]
-  type: testharness
-  [XMLHttpRequest: members during network errors (sync)]
-    expected: FAIL
-

tests/wpt/metadata/xhr/xmlhttprequest-network-error.htm.ini

@@ -1,5 +0,0 @@
-[xmlhttprequest-network-error.htm]
-  type: testharness
-  [XMLHttpRequest: members during network errors]
-    expected: FAIL
-