Support GZip encoding on the http server.

tests/standalone/io/http_compression_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.
+//
+// VMOptions=
+// VMOptions=--short_socket_read
+// VMOptions=--short_socket_write
+// VMOptions=--short_socket_read --short_socket_write
+
+import 'dart:io';
+
+void testServerCompress() {
+  var data = "My raw server provided data";

[Søren Gjesse, 2013/03/12 08:54:09]

Extend the test with a huge body ad well.

[Anders Johnsen, 2013/03/12 10:04:59]

Done.

+  HttpServer.bind().then((server) {
+    server.listen((request) {
+      request.response.write(data);
+      request.response.close();
+    });
+    var client = new HttpClient();
+    client.get("localhost", server.port, "/")
+        .then((request) {
+          request.headers.set(HttpHeaders.ACCEPT_ENCODING, "gzip");
+          return request.close();
+        })
+        .then((response) {

[Søren Gjesse, 2013/03/12 08:54:09]

Check that Content-Encoding is gzip.

[Anders Johnsen, 2013/03/12 10:04:59]

Done.

+          response
+              .transform(new ZLibInflater())
+              .transform(new StringDecoder())
+              .reduce(new StringBuffer(), (buffer, str) {
+                buffer.write(str);
+                return buffer;
+              }).then((buffer) {
+                Expect.equals(data, buffer.toString());
+                server.close();
+                client.close();
+              });
+        });
+  });
+}
+
+void main() {
+  testServerCompress();
+}