Support redirect to relative Uri, as specified by rfc3986#4.2.

tests/standalone/io/http_redirect_test.dart

 // Copyright (c) 2013, 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 "package:expect/expect.dart";
 import "dart:async";
 import "dart:io";
 import "dart:uri";
 
@@ skipping 39 matching lines @@
          response.close();
        }
     );
     addRequestHandler(
        "/location",
        (HttpRequest request, HttpResponse response) {
          response.close();
        }
     );
 
+    // Setup redirects with relative url.
+    addRequestHandler(
+       "/redirectUrl",
+       (HttpRequest request, HttpResponse response) {
+         response.headers.set(HttpHeaders.LOCATION, "/some/relativeUrl");
+         response.statusCode = HttpStatus.MOVED_PERMANENTLY;
+         response.close();
+       }
+    );
+
+    addRequestHandler(
+       "/some/redirectUrl",
+       (HttpRequest request, HttpResponse response) {
+         response.headers.set(HttpHeaders.LOCATION, "relativeUrl");
+         response.statusCode = HttpStatus.MOVED_PERMANENTLY;
+         response.close();
+       }
+    );
+
+    addRequestHandler(
+       "/some/relativeUrl",
+       (HttpRequest request, HttpResponse response) {
+         response.close();
+       }
+    );
+
+    addRequestHandler(
+       "/redirectUrl2",
+       (HttpRequest request, HttpResponse response) {
+         response.headers.set(HttpHeaders.LOCATION, "location");
+         response.statusCode = HttpStatus.MOVED_PERMANENTLY;
+         response.close();
+       }
+    );
+
+    addRequestHandler(
+       "/redirectUrl3",
+       (HttpRequest request, HttpResponse response) {
+         response.headers.set(HttpHeaders.LOCATION, "./location");
+         response.statusCode = HttpStatus.MOVED_PERMANENTLY;
+         response.close();
+       }
+    );
+
+    addRequestHandler(
+       "/redirectUrl4",
+       (HttpRequest request, HttpResponse response) {
+         response.headers.set(HttpHeaders.LOCATION, "./a/b/../../location");
+         response.statusCode = HttpStatus.MOVED_PERMANENTLY;
+         response.close();
+       }
+    );
+
+    addRequestHandler(
+       "/redirectUrl5",
+       (HttpRequest request, HttpResponse response) {
+         response.headers.set(HttpHeaders.LOCATION,
+                              "//127.0.0.1:${server.port}/location");
+         response.statusCode = HttpStatus.MOVED_PERMANENTLY;
+         response.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 293 matching lines @@
               (_) {},
               onDone: () {
                 Expect.equals(1, response.redirects.length);
                 server.close();
                 client.close();
               });
           });
   });
 }
 
+void testRedirectRelativeUrl() {
+  testPath(String path) {
+    setupServer().then((server) {
+      HttpClient client = new HttpClient();
+
+      print(path);
+      client.getUrl(Uri.parse("http://127.0.0.1:${server.port}$path"))
+          .then((request) => request.close())
+          .then((response) {
+            response.listen(
+                (_) {},
+                onDone: () {
+                  Expect.equals(HttpStatus.OK, response.statusCode);
+                  Expect.equals(1, response.redirects.length);
+                  server.close();
+                  client.close();
+                });
+            });
+    });
+  }
+  testPath("/redirectUrl");
+  testPath("/some/redirectUrl");
+  testPath("/redirectUrl2");
+  testPath("/redirectUrl3");
+  testPath("/redirectUrl4");
+  testPath("/redirectUrl5");
+}
+
 main() {
   testManualRedirect();
   testManualRedirectWithHeaders();
   testAutoRedirect();
   testAutoRedirectWithHeaders();
   testAutoRedirect301POST();
   testAutoRedirect303POST();
   testAutoRedirectLimit();
   testRedirectLoop();
   testRedirectClosingConnection();
+  testRedirectRelativeUrl();
 }