Fix multiple onRequest callbacks during redirect.

tests/standalone/io/http_redirect_test.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 
 #import("dart:io");
 #import("dart:uri");
 
 HttpServer setupServer() {
   HttpServer server = new HttpServer();
   server.listen("127.0.0.1", 0, backlog: 5);
 
   void addRedirectHandler(int number, int statusCode) {
     server.addRequestHandler(
        (HttpRequest request) => request.path == "/$number",
        (HttpRequest request, HttpResponse response) {
        response.headers.set(HttpHeaders.LOCATION,
                             "http://127.0.0.1:${server.port}/${number + 1}");
        response.statusCode = statusCode;
        response.outputStream.close();
      });
   }
 
+  // Setup simple redirect.
+  server.addRequestHandler(
+     (HttpRequest request) => request.path == "/redirect",
+     (HttpRequest request, HttpResponse response) {
+       response.headers.set(HttpHeaders.LOCATION,
+                            "http://127.0.0.1:${server.port}/location");
+       response.statusCode = HttpStatus.MOVED_PERMANENTLY;
+       response.outputStream.close();
+     }
+  );
+  server.addRequestHandler(
+     (HttpRequest request) => request.path == "/location",
+     (HttpRequest request, HttpResponse response) {
+       response.outputStream.close();
+     }
+  );
+
   // Setup redirect chain.
   int n = 1;
   addRedirectHandler(n++, HttpStatus.MOVED_PERMANENTLY);
   addRedirectHandler(n++, HttpStatus.MOVED_TEMPORARILY);
   addRedirectHandler(n++, HttpStatus.SEE_OTHER);
   addRedirectHandler(n++, HttpStatus.TEMPORARY_REDIRECT);
   for (int i = n; i < 10; i++) {
     addRedirectHandler(i, HttpStatus.MOVED_PERMANENTLY);
   }
 
@@ skipping 53 matching lines @@
         client.shutdown();
       }
     };
   };
 }
 
 void testAutoRedirect() {
   HttpServer server = setupServer();
   HttpClient client = new HttpClient();
 
+  var requestCount = 0;
+
+  void onRequest(HttpClientRequest request) {
+    requestCount++;
+    request.outputStream.close();
+  }
+
+  void onResponse(HttpClientResponse response) {
+    response.inputStream.onData =
+        () => Expect.fail("Response data not expected");
+    response.inputStream.onClosed = () {
+      Expect.equals(1, requestCount);
+      server.close();
+      client.shutdown();
+    };
+  };
+
+  HttpClientConnection conn =
+      client.getUrl(
+          new Uri.fromString("http://127.0.0.1:${server.port}/redirect"));
+  conn.onRequest = onRequest;
+  conn.onResponse = onResponse;
+  conn.onError = (e) => Expect.fail("Error not expected ($e)");
+}
+
+void testAutoRedirectLimit() {
+  HttpServer server = setupServer();
+  HttpClient client = new HttpClient();
+
   HttpClientConnection conn =
       client.getUrl(new Uri.fromString("http://127.0.0.1:${server.port}/1"));
   conn.onResponse = (HttpClientResponse response) {
     response.inputStream.onData = () => Expect.fail("Response not expected");
     response.inputStream.onClosed = () => Expect.fail("Response not expected");
   };
   conn.onError = (e) {
     Expect.isTrue(e is RedirectLimitExceededException);
     Expect.equals(5, e.redirects.length);
     server.close();
@@ skipping 16 matching lines @@
     Expect.isTrue(e is RedirectLoopException);
     Expect.equals(2, e.redirects.length);
     server.close();
     client.shutdown();
   };
 }
 
 main() {
   testManualRedirect();
   testAutoRedirect();
+  testAutoRedirectRequestBody();
+  testAutoRedirectLimit();
   testRedirectLoop();
 }