FULL PRODUCT VERSION :
java version "1.8.0_152"
Java(TM) SE Runtime Environment (build 1.8.0_152-b16)
Java HotSpot(TM) 64-Bit Server VM (build 25.152-b16, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Darwin iMac-Marcin 17.3.0 Darwin Kernel Version 17.3.0: Thu Nov 9 18:09:22 PST 2017; root:xnu-4570.31.3~1/RELEASE_X86_64 x86_64

A DESCRIPTION OF THE PROBLEM :
Returned generic type which is declared from inner public classes loses original type.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
I provided code below


ERROR MESSAGES/STACK TRACES THAT OCCUR :
Error:(7, 55) java: cannot find symbol
  symbol: method getActionButtonEvent()
  location: class com.marurban.BaseViewModel<com.marurban.FavoriteLeaguesViewModel.Accessor,com.marurban.FavoriteLeaguesViewModel.ViewEvents,com.marurban.FavoriteLeaguesViewModel.FlowEvents>.FlowEvents

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
public class Main {

    public static void main(String[] args) {

        new FavoriteLeaguesViewModel().getFlowEvents().getActionButtonEvent();
    }
}

public abstract class BaseViewModel<FlowEvents extends BaseViewModel.FlowEvents> {

    private FlowEvents flowEvents;

    public BaseViewModel() {
        flowEvents = createFlow();
    }

    protected abstract FlowEvents createFlow();

    public FlowEvents getFlowEvents() {
        return flowEvents;
    }

    public class FlowEvents {
    }
}

public abstract class FavoritesViewModel<FlowEvents extends FavoritesViewModel.FlowEvents>
        extends BaseViewModel<FlowEvents> {

    List list;

    public FavoritesViewModel() {
        super();
    }

    public abstract class FlowEvents extends BaseViewModel.FlowEvents {

        public List getActionButtonEvent() {
            return list;
        }
    }
}


public class FavoriteLeaguesViewModel extends FavoritesViewModel<FavoriteLeaguesViewModel.FlowEvents> {

    public FavoriteLeaguesViewModel() {
        super();
    }

    @Override
    protected FlowEvents createFlow() {
        return new FlowEvents();
    }

    public class FlowEvents extends FavoritesViewModel.FlowEvents {

    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
You need to explicitly cast to proper class.

public class Main {

    public static void main(String[] args) {
        FavoriteLeaguesViewModel viewModel = new FavoriteLeaguesViewModel();
        FavoriteLeaguesViewModel.FlowEvents flowEvents = (FavoriteLeaguesViewModel.FlowEvents) viewModel.getFlowEvents();
        flowEvents.getActionButtonEvent();
    }
}