Summary:
Implement common interface efl_ui_progress and inherit slider and progressbar from common interface.
Currently legacy APIs will also call interface functions and later it can be deprecated.
This interface will be moved to EFL in src/lib/efl/interfaces when elementary is merged into efl.
Test Plan:
elementary_test -to 'slider'
elementary_test -to 'progressbar'
Reviewers: singh.amitesh, raster, tasn, felipealmeida, woohyun, cedric, jpeg
Subscribers: saurabhbunty, alok25
Differential Revision: https://phab.enlightenment.org/D3759
Yeshwanth Reddivari
Cedric BAIL