genlist : add size_calc forcely about content when elm_layout.

genlist : add size_calc forcely about content when elm_layout.

Summary:
If the content object of genlist item is 'elm_layout' class,
minimum size cannot get directly becuase layout do the delay calculating.
So to make proper genlist size calc, before the swallowing,
forcely do the size calc about layout class contents in genlist.

@fix

Test Plan: N/A

Reviewers: raster, cedric, singh.amitesh, Hermet

Reviewed By: Hermet

Subscribers: seoz, conr2d, eagleeye

Differential Revision: https://phab.enlightenment.org/D3478

Change-Id: I1678cdb0e288db356cb2631f54bc37c8c6492294