Auto merge of #21988 - CYBAI:drop-promises, r=jdm

Clear refcounted promise before dropping JSRuntime

Not sure if this is the right solution?

I also tried to `impl Drop for LiveDOMReferences` but it's still executed after dropping JSRuntime.
So, maybe we should clear it before dropping the JSRuntime?

cc @jdm @asajeffrey

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #21331 .
- [x] There are tests for these changes; the status of `fetch/cross-origin-resource-policy/fetch-in-iframe.html` will be `OK`

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components/script/dom/bindings/refcounted.rs

@@ -224,6 +224,12 @@ impl LiveDOMReferences {
         });
     }
 
+    pub fn destruct() {
+        LIVE_REFERENCES.with(|ref r| {
+            *r.borrow_mut() = None;
+        });
+    }
+
     #[allow(unrooted_must_root)]
     fn addref_promise(&self, promise: Rc<Promise>) {
         let mut table = self.promise_table.borrow_mut();

components/script/script_runtime.rs

@@ -271,7 +271,10 @@ pub struct Runtime(RustRuntime);
 
 impl Drop for Runtime {
     fn drop(&mut self) {
-        THREAD_ACTIVE.with(|t| t.set(false));
+        THREAD_ACTIVE.with(|t| {
+            LiveDOMReferences::destruct();
+            t.set(false);
+        });
     }
 }