chore: align fetch to spec (#10203)

This commit aligns the `fetch` API and the `Request` / `Response`
classes belonging to it to the spec. This commit enables all the
relevant `fetch` WPT tests. Spec compliance is now at around 90%.

Performance is essentially identical now (within 1% of 1.9.0).

1 files changed, 4 insertions, 6 deletions

diff --git a/runtime/ops/http.rs b/runtime/ops/http.rs
index bdef14594..4d9787cde 100644
--- a/runtime/ops/http.rs
+++ b/runtime/ops/http.rs
@@ -331,7 +331,7 @@ struct RespondArgs(
   // status:
   u16,
   // headers:
-  Vec<String>,
+  Vec<(String, String)>,
 );
 
 async fn op_http_response(
@@ -358,11 +358,9 @@ async fn op_http_response(
 
   let mut builder = Response::builder().status(status);
 
-  debug_assert_eq!(headers.len() % 2, 0);
-  let headers_count = headers.len() / 2;
-  builder.headers_mut().unwrap().reserve(headers_count);
-  for i in 0..headers_count {
-    builder = builder.header(&headers[2 * i], &headers[2 * i + 1]);
+  builder.headers_mut().unwrap().reserve(headers.len());
+  for (key, value) in &headers {
+    builder = builder.header(key, value);
   }
 
   let res;