Remove incorrect request error handling

std/http/server.ts

@@ -472,13 +472,11 @@ class EventType<T> {
 }
 
 export class Server implements AsyncIterable<ServerRequest> {
-  private closing = false;
   private closed = deferred<void>();
 
   constructor(public listener: Listener) {}
 
   close(): void {
-    this.closing = true;
     this.closed.resolve();
     this.listener.close();
   }
@@ -489,17 +487,15 @@ export class Server implements AsyncIterable<ServerRequest> {
   ): AsyncIterableIterator<ServerRequest> {
     const bufr = new BufReader(conn);
     const w = new BufWriter(conn);
-    let req: ServerRequest | Deno.EOF;
-    let err: Error | undefined;
 
     while (true) {
+      let req: ServerRequest | Deno.EOF;
       try {
         req = await Promise.race([
           readRequest(conn, bufr),
           this.closed.then((): Deno.EOF => Deno.EOF)
         ]);
       } catch (e) {
-        err = e;
         break;
       }
       if (req === Deno.EOF) {
@@ -520,24 +516,6 @@ export class Server implements AsyncIterable<ServerRequest> {
       }
     }
 
-    if (req === Deno.EOF) {
-      // The connection was gracefully closed.
-    } else if (err && req) {
-      // An error was thrown while parsing request headers.
-      try {
-        await writeResponse(req.w, {
-          status: 400,
-          body: encoder.encode(`${err.message}\r\n\r\n`)
-        });
-      } catch (_) {
-        // The connection is destroyed.
-        // Ignores the error.
-      }
-    } else if (this.closing) {
-      // There are more requests incoming but the server is closing.
-      // TODO(ry): send a back a HTTP 503 Service Unavailable status.
-    }
-
     conn.close();
   }