widget: Fix a bug in elm_widget_newest_focus_order_get.
widget: Fix a bug in elm_widget_newest_focus_order_get.

When elm_widget_newest_focus_order_get is called with can_focus_only,
only focusable objects should be the candidates for newest focused object.
But there are cases that unfocusable object add +1 to newest_focus_order.

tasn/elementary,FlorentRevest/Elementary,rvandegrift/elementary,rvandegrift/elementary,rvandegrift/elementary,rvandegrift/elementary,FlorentRevest/Elementary,FlorentRevest/Elementary,tasn/elementary,tasn/elementary,tasn/elementary,FlorentRevest/Elementary,tasn/elementary