Returning result from a page after state restoration

[BarashkovaElena]

qlevar_router allows to return the result from a page this way: final result = await QR.to<String>('/page', waitForResult: true);

This works fine until we want to support state restoration on android. Consider the following steps:

1. Configure the app with qlevar_router with state restoration enabled.
2. Enable "don't keep activities" flag on Android device.
3. Start the app and open a page with waitForResult = true
4. Put the app to background, causing it to be killed by the system.
5. Go back to the app, so that its state and route is restored.
6. Close the currently opened page by calling QR.back('result')

The caller page will not receive this result.

I haven't found a way to pass result in a way that survives state restoration. Would be helpful to have this option.