efl.extra part is extra part of the layout swallow,
which can be generally used on overall layout object.
To be supported layout part infrastructures,
add efl.extra on layout_swallow_part list.
Depends on D9233
Hi. sorry for late answer.
This was discussed in D8582
that elm.swallow.end is not eidetic name, so replace the name to extra.
I won't delete the efl.end on the list yet for safety,
but I think the best option is replace all efl.end to efl.extra.
if you agree I will update the patch and replace all efl.end usage.( seems only text.edc are using this name...)
and as far as I remember,
there are some issue that cannot using efl_part on content_set property if the part is not in the layout_swallow_parts list..... I think for the extension of efl_part usage, also need to fix this issue.