[MOD-2344] iOS: Ti.Map - MapView not drawing polygon in some cases

From the community on Github: {quote} Hi, thanks for the module! I ran into a situation where a convoluted set of user actions on iOS (device rotation, textfield focus/blur, tab swapping) ended up getting the MKMapView into a state where if I called mapView.addPolygons from the JS, they wouldn't actually render until the map was zoomed or panned. This was the only successful workaround I could find. I also tried posting different combinations of setNeedsDisplay, invalidatePath, and setNeedsLayout on both the current and main queue for the mapview as well as the overlay renderer. That said, it was a tough bug to reproduce so its possible that this doesnt actually fix things in the end. {quote} PR: https://github.com/appcelerator-modules/ti.map/pull/205