edje/optimization: refactor edje_color_class_set() api.

edje/optimization: refactor edje_color_class_set() api.

Summary:
During _elm_config_color_overlay_apply() application can call this api
100's of time depending on how many overlay it wants add . As each color_class
set triggers the global color class apply chain 3 times (for color , outline and shadow)
just club them once and emit single color_class,set event.

Reviewers: Hermet, ali.alzyod, zmike

Reviewed By: zmike

Subscribers: cedric, #reviewers, #committers

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D9784