fix: poll connection after writing response chunk in Deno.serveHttp() (#10961)

This commit changes "op_http_response_write" to first send response chunk
and then poll the underlying HTTP connection.

Previously after writing a chunk of response HTTP connection wasn't polled
and thus data wasn't written to the socket until after next op interacting 
with the connection.

1 files changed, 4 insertions, 1 deletions

diff --git a/runtime/ops/http.rs b/runtime/ops/http.rs
index 11e83f6c7..3e8a4ada7 100644
--- a/runtime/ops/http.rs
+++ b/runtime/ops/http.rs
@@ -502,6 +502,9 @@ async fn op_http_response_write(
   let mut send_data_fut = body.send_data(Vec::from(&*buf).into()).boxed_local();
 
   poll_fn(|cx| {
+    let r = send_data_fut.poll_unpin(cx).map_err(AnyError::from);
+
+    // Poll connection so the data is flushed
     if let Poll::Ready(Err(e)) = conn_resource.poll(cx) {
       // close ConnResource
       // close RequestResource associated with connection
@@ -509,7 +512,7 @@ async fn op_http_response_write(
       return Poll::Ready(Err(e));
     }
 
-    send_data_fut.poll_unpin(cx).map_err(AnyError::from)
+    r
   })
   .await?;