title: Could not load source 'dart:_http/http_impl.dart': <source not available>
body: <p>My flutter app is crashing and showing this error "Could not load source 'dart:_http/http_impl.dart': ."
  My pub file</p>
  
  <pre><code>name: name_here description: A new Flutter project.
  
  # The following defines the version and build number for your application.
  # A version number is three numbers separated by dots, like 1.2.43
  # followed by an optional build number separated by a +.
  # Both the version and the builder number may be overridden in flutter
  # build by specifying --build-name and --build-number, respectively.
  # Read more about versioning at semver.org. version: 1.0.0+1
  
  environment:   sdk: "&gt;=2.0.0-dev.68.0 &lt;3.0.0"
  
  dependencies:   flutter:
      sdk: flutter
  
    banner: ^0.1.3   cloud_firestore: ^0.8.2  
      # The following adds the Cupertino Icons font to your application.   # Use with the CupertinoIcons class for iOS style icons.   cupertino_icons: ^0.1.2   sqflite: any   flutter_rating: ^0.0.2   flutter_firebase_ui: ^0.0.12  
  
  dev_dependencies:   flutter_test:
      sdk: flutter
  
  
  # For information on the generic Dart part of this file, see the
  # following page: https://www.dartlang.org/tools/pub/pubspec
  
  # The following section is specific to Flutter. flutter:
  
    # The following line ensures that the Material Icons font is   # included with your application, so that you can use the icons in   # the material Icons class.   uses-material-design: true
  
    # To add assets to your application, add an assets section, like this:   # assets:   #  - images/a_dot_burr.jpeg   #  - images/a_dot_ham.jpeg
  
    # An image asset can refer to one or more resolution-specific "variants", see   # https://flutter.io/assets-and-images/#resolution-aware.
  
    # For details regarding adding assets from package dependencies, see
  # https://flutter.io/assets-and-images/#from-packages
  
    # To add custom fonts to your application, add a fonts section here,
  # in this "flutter" section. Each entry in this list should have a   # "family" key with the font family name, and a "fonts" key with a   # list giving the asset and other descriptors for the font. For   # example:   # fonts:   #   - family: Schyler   #     fonts:   #       - asset: fonts/Schyler-Regular.ttf   #       - asset: fonts/Schyler-Italic.ttf   #         style: italic   #   - family: Trajan Pro   #     fonts:   #       - asset: fonts/TrajanPro.ttf   #  
  - asset: fonts/TrajanPro_Bold.ttf   #         weight: 700   #   # For details regarding fonts from package dependencies,   # see https://flutter.io/custom-fonts/#from-packages
  </code></pre>