Remove the http package from the repo.

pkg/http/lib/src/io.dart

-// Copyright (c) 2014, 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 http.io;
-
-@MirrorsUsed(targets: const ['dart.io.HttpClient', 'dart.io.HttpException',
-  'dart.io.File'])
-import 'dart:mirrors';
-
-/// Whether `dart:io` is supported on this platform.
-bool get supported => _library != null;
-
-/// The `dart:io` library mirror, or `null` if it couldn't be loaded.
-final _library = _getLibrary();
-
-/// The `dart:io` HttpClient class mirror.
-final ClassMirror _httpClient =
-    _library.declarations[const Symbol('HttpClient')];
-
-/// The `dart:io` HttpException class mirror.
-final ClassMirror _httpException =
-    _library.declarations[const Symbol('HttpException')];
-
-/// The `dart:io` File class mirror.
-final ClassMirror _file = _library.declarations[const Symbol('File')];
-
-/// Asserts that the [name]d `dart:io` feature is supported on this platform.
-///
-/// If `dart:io` doesn't work on this platform, this throws an
-/// [UnsupportedError].
-void assertSupported(String name) {
-  if (supported) return;
-  throw new UnsupportedError("$name isn't supported on this platform.");
-}
-
-/// Creates a new `dart:io` HttpClient instance.
-newHttpClient() => _httpClient.newInstance(const Symbol(''), []).reflectee;
-
-/// Creates a new `dart:io` File instance with the given [path].
-newFile(String path) => _file.newInstance(const Symbol(''), [path]).reflectee;
-
-/// Returns whether [error] is a `dart:io` HttpException.
-bool isHttpException(error) => reflect(error).type.isSubtypeOf(_httpException);
-
-/// Returns whether [client] is a `dart:io` HttpClient.
-bool isHttpClient(client) => reflect(client).type.isSubtypeOf(_httpClient);
-
-/// Tries to load `dart:io` and returns `null` if it fails.
-LibraryMirror _getLibrary() {
-  try {
-    return currentMirrorSystem().findLibrary(const Symbol('dart.io'));
-  } catch (_) {
-    // TODO(nweiz): narrow the catch clause when issue 18532 is fixed.
-    return null;
-  }
-}