efl_ui_stack: use direct events instead of event_animation

efl_ui_stack: use direct events instead of event_animation

event_animation of efl_canvas_object, is a little problem, we need to
explictly turn it off, to do a visual state manipulation, just to attach
the animation again. Further more, the animation objects are stored in
static fields, which are not bound to the object. Which means, when two
Efl.Ui.Stack objects are running in parrallel, the animation will look a
little bit wacky, since the object is detached before the animation is
ended.

ref T7555

Reviewed-by: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Differential Revision: https://phab.enlightenment.org/D8008