Rip out the last dart:io dependency from pkg/http.

pkg/http/test/client_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.
-
-library client_test;
-
-import 'dart:io';
-
-import 'package:http/http.dart' as http;
-import 'package:unittest/unittest.dart';
-
-import 'utils.dart';
-
-void main() {
-  tearDown(stopServer);
-
-  test('#send a StreamedRequest', () {
-    expect(startServer().then((_) {
-      var client = new http.Client();
-      var request = new http.StreamedRequest("POST", serverUrl);
-      request.headers[HttpHeaders.CONTENT_TYPE] =
-        'application/json; charset=utf-8';
-      request.headers[HttpHeaders.USER_AGENT] = 'Dart';
-
-      expect(client.send(request).then((response) {
-        expect(response.request, equals(request));
-        expect(response.statusCode, equals(200));
-        expect(response.headers['single'], equals('value'));
-        // dart:io internally normalizes outgoing headers so that they never
-        // have multiple headers with the same name, so there's no way to test
-        // whether we handle that case correctly.
-
-        return response.stream.bytesToString();
-      }).whenComplete(client.close), completion(parse(equals({
-        'method': 'POST',
-        'path': '/',
-        'headers': {
-          'content-type': ['application/json; charset=utf-8'],
-          'accept-encoding': ['gzip'],
-          'user-agent': ['Dart'],
-          'transfer-encoding': ['chunked']
-        },
-        'body': '{"hello": "world"}'
-      }))));
-
-      request.sink.add('{"hello": "world"}'.codeUnits);
-      request.sink.close();
-    }), completes);
-  });
-
-  test('#send with an invalid URL', () {
-    expect(startServer().then((_) {
-      var client = new http.Client();
-      var url = Uri.parse('http://http.invalid');
-      var request = new http.StreamedRequest("POST", url);
-      request.headers[HttpHeaders.CONTENT_TYPE] =
-          'application/json; charset=utf-8';
-
-      expect(client.send(request), throwsSocketException);
-
-      request.sink.add('{"hello": "world"}'.codeUnits);
-      request.sink.close();
-    }), completes);
-  });
-}