this is Flutter Plugin
impl applib acconding applib`s protocol
Since applib is an HTTP-based service, AppChannel exists to use these interfaces written in Dart.
It allows retrieving device information through Dart API calls.
Have no effect, just help to open android project
由于 applib 是一个基于 HTTP 的服务，所以 AppChannel 的存在是为了将这些接口使用 Dart 编写
可以以 Dart API 调用的方式获取设备的信息