You cannot run this project for the Flutter web tech preview because it has dependencies on 'flutter' and 'shared_preferences' which are not currently supported for web. The documentation at https://flutter.dev/web provides more details on the limitations of the Flutter web tech preview and which plugins are not compatible.

5. webdev could not run for this project.
You have a dependency on `flutter` which is not supported for
flutter_web tech preview. See https://flutter.dev/web for more details.
You have a dependency on `shared_preferences` which is not supported for
flutter_web tech preview. See https://flutter.dev/web for more details.
pub finished with exit code 78

7. // Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:async';
import 'package:flutter/services.dart';
import 'package:meta/meta.dart';
const MethodChannel _kChannel =
MethodChannel('plugins.flutter.io/shared_preferences');

9. import 'dart:html';
class Sample {
Storage storage = window.localStorage;
Sample() {
storage["hoge"] = "huga";
storage["hoge"]; // huga
}
}

10. https://saketco-buy.firebaseapp.com/