Remove the http package from the repo.

pkg/http/lib/src/base_response.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.
-
-library base_response;
-
-import 'base_request.dart';
-
-/// The base class for HTTP responses.
-///
-/// Subclasses of [BaseResponse] are usually not constructed manually; instead,
-/// they're returned by [BaseClient.send] or other HTTP client methods.
-abstract class BaseResponse {
-  /// The (frozen) request that triggered this response.
-  final BaseRequest request;
-
-  /// The status code of the response.
-  final int statusCode;
-
-  /// The reason phrase associated with the status code.
-  final String reasonPhrase;
-
-  /// The size of the response body, in bytes.
-  ///
-  /// If the size of the request is not known in advance, this is `null`.
-  final int contentLength;
-
-  // TODO(nweiz): automatically parse cookies from headers
-
-  // TODO(nweiz): make this a HttpHeaders object.
-  /// The headers for this response.
-  final Map<String, String> headers;
-
-  /// Whether this response is a redirect.
-  final bool isRedirect;
-
-  /// Whether the server requested that a persistent connection be maintained.
-  final bool persistentConnection;
-
-  /// Creates a new HTTP response.
-  BaseResponse(
-      this.statusCode,
-      {this.contentLength,
-       this.request,
-       this.headers: const {},
-       this.isRedirect: false,
-       this.persistentConnection: true,
-       this.reasonPhrase}) {
-    if (statusCode < 100) {
-      throw new ArgumentError("Invalid status code $statusCode.");
-    } else if (contentLength != null && contentLength < 0) {
-      throw new ArgumentError("Invalid content length $contentLength.");
-    }
-  }
-}