2.79 gave a visual hint if an object was linked (in other scenes or from
lib files) by coloring its origin blueish - seems this is useful
information to have because it so unintentional changes elsewhere (e.g
in other scenes) can be foreseen.
This was lost in the transition to 2.8, but it seems this was not
intentional because a check for this was still in the code. However,
checking users on the COW id wasnt working here (seems COW always have
zero users? - bit on shaky ground here), this patch checks the orig_id
instead [restoring the linked state indication].
notes:
- 2.79 actually also did this for selection outline (not sure this is
desired, could be added as well)
- in 2.79 being part of a group did not increase usercount whereas in
2.8 being part of multiple collections does (so this change will give
you the blueish indication as soon as this is the case - not totally
sure if this would be desired?)