Add test for filtered crossorigin cache response (#24356).

tests/wpt/mozilla/meta/MANIFEST.json

@@ -11353,6 +11353,12 @@
      {}
     ]
    ],
+   "mozilla/cache_crossorigin_response.sub.html": [
+    [
+     "mozilla/cache_crossorigin_response.sub.html",
+     {}
+    ]
+   ],
    "mozilla/calc.html": [
     [
      "mozilla/calc.html",
@@ -18479,6 +18485,10 @@
    "13a1a0fdc15ac05458ebf2c1fd75d501a6de92e3",
    "testharness"
   ],
+  "mozilla/cache_crossorigin_response.sub.html": [
+   "266995f30afa3e9b3472e4cc43be6493c562aef6",
+   "testharness"
+  ],
   "mozilla/calc.html": [
    "80aa06e2ae7cd5db585873f147a21382b279b86e",
    "testharness"

tests/wpt/mozilla/tests/mozilla/cache_crossorigin_response.sub.html

@@ -0,0 +1,31 @@
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script>
+  let t = async_test("Cached cross-origin response doesn't hang");
+
+  onload = t.step_func(function() {
+      let complete = 0;
+      function check() {
+          complete++;
+          if (complete == 2) {
+              t.done();
+          }
+      }
+
+      const url = "http://{{hosts[][www]]}}:{{ports[http][0]}}/html/semantics/scripting-1/the-script-element/is-script-goal.js?pipe=trickle(d5)|header(Cache-Control,max-age=3600)|header(Pragma,)|header(Expires,36000)";
+
+      function loadScript() {
+          let script = document.createElement('script');
+          document.body.appendChild(script);
+          script.src = url;
+          script.onerror = t.unreached_func();
+          script.onload = t.step_func(check);
+      }
+      // Kick off a load so there's a cache entry with an in progress response.
+      loadScript();
+
+      // Kick off a second load after a slight delay which should end up waiting until
+      // the first load is complete before sharing the existing cached response.
+      t.step_timeout(loadScript, 0);
+  });
+</script>