A tiny amount of logic/variable reside in ContentViewCore for joystick event handling/state management. Tiny as it is, it straddles on a few other flows (Ime/Focus/MotionEvent), having CVC keep them inside where all these flows go through, hence making it hard to decouple those flows. 

Since it is a kind of aux device (like gamepad), it would make sense to move what's in CVC to //device/joystick so that its state and flow can be referenced by other parts not only through/from CVC but directly from it if necessary.

The new device dir will have following contents:
 - status indicating joystick scroll is enabled 
 - logic that converts generic motion event to fling action that emulates joystick scroll


One possible refactoring around it would be to let joystick use ui/ (EventForwarder) to send down scroll/fling events to native like other events already being handled there. This direction of changes helps break up CVC further (i.e. deleting more interface methods defined for ContentView - ContentViewCore).

This raises a follow-up refactoring possibility of moving scroll/fling-related parts out of content/, probably to ui. All these scroll-related actions look like good fit for being routed to RenderWidgetHostViewAndroid through ViewAndroid hierarchy without going through native CVC.