Make VerticalScrollNativeTrait not fail if there is not gestureManager.
Make VerticalScrollNativeTrait not fail if there is not gestureManager.

mdittmer/foam,osric-the-knight/foam,jacksonic/foam,foam-framework/foam,foam-framework/foam,osric-the-knight/foam,jacksonic/foam,foam-framework/foam,jlhughes/foam,mdittmer/foam,jlhughes/foam,mdittmer/foam,jacksonic/foam,osric-the-knight/foam,jacksonic/foam,foam-framework/foam,mdittmer/foam,jlhughes/foam,jlhughes/foam,foam-framework/foam,osric-the-knight/foam