Summary:
This uses constructor/destructor instead of group_add/group_del.
Note: finalize can't be used for theme loading as any action done
inside
efl_add(...) would be lost (eg. part text set).
Test Plan: 1) run elementary_test -to radio
Reviewers: jpeg, woohyun, cedric
Subscribers: akanad
Differential Revision: https://phab.enlightenment.org/D5404
Signed-off-by: Cedric BAIL <cedric@osg.samsung.com>