Auto merge of #21933 - notriddle:navigation-redirect-status-code, r=nox

Thread the status through navigation redirects

This is necessary because status codes affect whether the redirect is done with the same HTTP method or a different one.

This is part of #21886, but there's also a flaw in how iframes are handled that is causing the redirect to take over the entire window, so this commit doesn't entirely fix slither.io.

---
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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 are part of #21886, but more changes are needed to actually fix it

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

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components/constellation/network_listener.rs

@@ -113,6 +113,9 @@ impl NetworkListener {
                             location_url: metadata.location_url.clone(),
                             headers: headers.clone().into_inner(),
                             referrer: metadata.referrer.clone(),
+                            status_code: metadata.status.as_ref()
+                                .map(|&(code, _)| code)
+                                .unwrap_or(200),
                         });
 
                         // XXXManishearth we don't have the cancel_chan anymore and

components/net_traits/response.rs

@@ -82,6 +82,7 @@ pub struct ResponseInit {
             serialize_with = "::hyper_serde::serialize")]
     #[ignore_malloc_size_of = "Defined in hyper"]
     pub headers: Headers,
+    pub status_code: u16,
     pub referrer: Option<ServoUrl>,
     pub location_url: Option<Result<ServoUrl, String>>,
 }
@@ -147,6 +148,7 @@ impl Response {
         res.location_url = init.location_url;
         res.headers = init.headers;
         res.referrer = init.referrer;
+        res.status = Some(StatusCode::from_u16(init.status_code));
         res
     }
 

tests/wpt/metadata/MANIFEST.json

@@ -283001,6 +283001,11 @@
      {}
     ]
    ],
+   "fetch/redirect-navigate/302-found-post-handler.py": [
+    [
+     {}
+    ]
+   ],
    "fetch/sec-metadata/README.md": [
     [
      {}
@@ -359258,6 +359263,12 @@
      {}
     ]
    ],
+   "fetch/redirect-navigate/302-found-post.html": [
+    [
+     "/fetch/redirect-navigate/302-found-post.html",
+     {}
+    ]
+   ],
    "fetch/sec-metadata/embed.tentative.https.sub.html": [
     [
      "/fetch/sec-metadata/embed.tentative.https.sub.html",
@@ -601413,6 +601424,14 @@
    "faaee86734e93bb514095e34671a57e00bcbcd98",
    "testharness"
   ],
+  "fetch/redirect-navigate/302-found-post-handler.py": [
+   "23bf4b2c522b7c00ab6bd0fc3eb99f0737d512ec",
+   "support"
+  ],
+  "fetch/redirect-navigate/302-found-post.html": [
+   "854cd329a8f12052bb79f35dd80268f246a52afd",
+   "testharness"
+  ],
   "fetch/sec-metadata/README.md": [
    "c460aa1ecb941118b6999209ba4601eb145a61b9",
    "support"

tests/wpt/web-platform-tests/fetch/redirect-navigate/302-found-post-handler.py

@@ -0,0 +1,13 @@
+def main(request, response):
+    if request.method == "POST":
+        response.add_required_headers = False
+        response.writer.write_status(302)
+        response.writer.write_header("Location", request.url)
+        response.writer.end_headers()
+        response.writer.write("")
+    elif request.method == "GET":
+        return ([("Content-Type", "text/plain")],
+                "OK")
+    else:
+        return ([("Content-Type", "text/plain")],
+                "FAIL")

tests/wpt/web-platform-tests/fetch/redirect-navigate/302-found-post.html

@@ -0,0 +1,20 @@
+<!DOCTYPE html>
+<!-- Step 1: send POST request to a URL which will then 302 Found redirect -->
+<title>HTTP 302 Found POST Navigation Test</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script>
+async_test(function(t) {
+  window.addEventListener("load", function() {
+    var frame = document.getElementById("frame");
+    var link = new URL("302-found-post-handler.py", window.location.href);
+    frame.contentWindow.document.body.innerHTML = '<form action="' + link.href + '" method="POST" id="form"><input name="n"></form>';
+    frame.contentWindow.document.getElementById("form").submit();
+    frame.addEventListener("load", t.step_func_done(function() {
+      assert_equals(frame.contentWindow.document.body.textContent, "OK");
+    }));
+  });
+}, "HTTP 302 Found POST Navigation");
+</script>
+<body>
+<iframe id="frame" src="about:blank"></iframe>