widget: set the parent-child relation again, when the widget is unset

Summary:
When the widget is unset from any container, a parent of the widget
doesn't exist. So we should set its parent to the top object.
But if we just set sd->parent, the parent can not find the widget as a
child. So the container widgets set the parent-child relation when
sub object is unset.
This commit is related to 0822ad2195d335d65208856e6e590ac47691d920.

@fix

Test Plan:
Check this issue.
https://phab.enlightenment.org/D3855
The unset widget don't added any widget as child.
So when it set scale, the widget can not reload the thmeme.

Reviewers: raster, cedric, Hermet, reutskiy.v.v

Reviewed By: Hermet, reutskiy.v.v

Subscribers: cedric, jpeg

Differential Revision: https://phab.enlightenment.org/D3957

Conflicts:
	src/lib/elementary/elm_mapbuf.c

1 files changed, 2 insertions, 2 deletions

diff --git a/src/lib/elementary/elm_scroller.c b/src/lib/elementary/elm_scroller.c
index 27f710dd6e..2862ae5150 100644
--- a/src/lib/elementary/elm_scroller.c
+++ b/src/lib/elementary/elm_scroller.c
@@ -827,9 +827,9 @@ _elm_scroller_content_unset(Eo *obj, Elm_Scroller_Data *sd, const char *part)
 
    ret = sd->content;
    if (sd->loop_h || sd->loop_v)
-     elm_widget_sub_object_del(obj, sd->contents);
+     _elm_widget_sub_object_redirect_to_top(obj, sd->contents);
    else
-     elm_widget_sub_object_del(obj, sd->content);
+     _elm_widget_sub_object_redirect_to_top(obj, sd->content);
    elm_interface_scrollable_content_set(obj, NULL);
    sd->content = NULL;