widget: Make focus_mouse_up_handle internal

I don't think this belongs to the public EO API.

Ref T5363

src/lib/elementary/elm_widget.c

@@ -4332,9 +4332,12 @@ _elm_widget_focus_hide_handle(Eo *obj, Elm_Widget_Smart_Data *_pd EINA_UNUSED)
    _if_focused_revert(obj, EINA_TRUE);
 }
 
-EOLIAN static void
-_elm_widget_focus_mouse_up_handle(Eo *obj, Elm_Widget_Smart_Data *pd)
+/* internal */
+EAPI void
+elm_widget_focus_mouse_up_handle(Eo *obj)
 {
+   Elm_Widget_Smart_Data *pd = efl_data_scope_get(obj, MY_CLASS);
+
    if (!_is_focusable(obj)) return;
 
    elm_obj_widget_focus_steal(obj, NULL);

src/lib/elementary/elm_widget.eo

@@ -369,10 +369,6 @@ abstract Elm.Widget (Efl.Canvas.Group, Elm.Interface.Atspi_Accessible,
          }
          return: bool; [[$true if this widget can handle focus, $false otherwise]]
       }
-      /* FIXME: Needs better doc... maybe merge with widget_event? */
-      focus_mouse_up_handle {
-         [[Handle focus mouse up]]
-      }
 
       /* Scroll API. */
       @property on_show_region_hook @protected {