feat(ext/http): abort event when request is cancelled (#26781)

```js
Deno.serve(async (req) => {
  const { promise, resolve } = Promise.withResolvers<void>();

  req.signal.addEventListener("abort", () => {
    resolve();
  });

  await promise;

  return new Response("Ok");
});
```

1 files changed, 10 insertions, 0 deletions

diff --git a/ext/http/service.rs b/ext/http/service.rs
index 75f93d77c..ce24dea43 100644
--- a/ext/http/service.rs
+++ b/ext/http/service.rs
@@ -27,6 +27,7 @@ use std::rc::Rc;
 use std::task::Context;
 use std::task::Poll;
 use std::task::Waker;
+use tokio::sync::oneshot;
 
 pub type Request = hyper::Request<Incoming>;
 pub type Response = hyper::Response<HttpRecordResponse>;
@@ -211,6 +212,7 @@ pub struct UpgradeUnavailableError;
 
 struct HttpRecordInner {
   server_state: SignallingRc<HttpServerState>,
+  closed_channel: Option<oneshot::Sender<()>>,
   request_info: HttpConnectionProperties,
   request_parts: http::request::Parts,
   request_body: Option<RequestBodyState>,
@@ -276,6 +278,7 @@ impl HttpRecord {
       response_body_finished: false,
       response_body_waker: None,
       trailers: None,
+      closed_channel: None,
       been_dropped: false,
       finished: false,
       needs_close_after_finish: false,
@@ -312,6 +315,10 @@ impl HttpRecord {
     RefMut::map(self.self_mut(), |inner| &mut inner.needs_close_after_finish)
   }
 
+  pub fn on_cancel(&self, sender: oneshot::Sender<()>) {
+    self.self_mut().closed_channel = Some(sender);
+  }
+
   fn recycle(self: Rc<Self>) {
     assert!(
       Rc::strong_count(&self) == 1,
@@ -390,6 +397,9 @@ impl HttpRecord {
     inner.been_dropped = true;
     // The request body might include actual resources.
     inner.request_body.take();
+    if let Some(closed_channel) = inner.closed_channel.take() {
+      let _ = closed_channel.send(());
+    }
   }
 
   /// Complete this record, potentially expunging it if it is fully complete (ie: cancelled as well).