I killed the dragon in an ancient world (version 1.8.8), then I wanted to resurrect the dragon in the snap-version 15w44a version (I did the new "rite" with EnderCrystal) and nothing happened ... did not happen animation, not new pillars were created, the dragon did not appear, absolutely nothing ...
I tried to kill the dragon in snap-version 15w44a, and then resurrect in same version, and it worked.
Confirmed for
15w44a Even if it worked it is pretty hard to find the position where the new portal would be, so probably some kind of indication would be needed as in 1.8 and earlier the portal was not necessarily at X=0 and Z=0.