Steps to reproduce:

1) Download attached projetc "case_808387 repro" and open in Unity.
2) Open scene "mecanim_crossfade_test".
3) Select "GameObject" in Hierarchy tab.
4) Press Play and go to Animator window.
5) You should see the Any State -> scale_some transition constantly being interrupted by the scale_some -> Empty transition. (see attached gif"anim_interrupting").
6) Select the Transition between Any State -> scale_some. Change the Interuption Source to Current State, check the Ordered Interruption box, set the Interruption Source back to Next State. Note that the Ordered Interruption box is greyed out but stays checked.
Note: You should now see the Any State -> scale_some transition reliably finish, with no more interruptions from the scale_some -> Empty transition.(see attached gif"anim_not_interrupting").

Reproduced with: 5.2.4f1, 5.3.5p7, 5.4.0b25, 5.5.0a2.