Summary:
Currently the focus was only on popup-content and popup-action area.
New API elm_layout_content_swallow_list_get() which returns the list of
swallow parts.
Test Plan: elementary_test -to popup. click on "subpopup + X button"
Reviewers: seoz, raster, woohyun
Reviewed By: raster
CC: nirajkr, aryarockstar, kashish
Differential Revision: https://phab.enlightenment.org/D375
This allows to select an axis that the layout will use its current size
to restrict the min size calculation of the inner edje, possibly helping
with textblock min size issues