Add Android and iOS modules to allow compilation on mobile platforms

[gibutm]

Presently the plugin only supports Desktop platforms (macos, linux and windows). When compiling a project that depends on desktop_window for mobile platform (android and ios), compilation will always fail as there are no modules set up for this plugin. I'm not sure if this plugin could have an overloaded usage for the mobile platform but a simple no-op implementation would be useful to allow consumption in projects that have a single codebase for mobile and desktop platforms.

What do you think? I am willing to raise a PR if that helps.

[Robert3141]

A solution to this is to wrap all of the references to this package in the conditon below:

import
if (kIsWeb
      ? false
      : Platform.isWindows || Platform.isLinux || Platform.isMacOS) {
}