Hello.

I know that Vindicators named "Johnny" can attack any kind of mob, (source):

http://minecraft.gamepedia.com/Vindicator#Behavior

I just noticed that Vindicators named "Johnny" in Minecraft PE doesn't attack any mob. only the default mobs "such as players, Villagers and Iron and Snow golems."

I used to rename a spawn egg via anvil in the name of "Johnny". However nothing changes.
Also i used a name tag in it and nothing change.

You can also try it. I used it in all of difficulty.

I'm using PGN-518 (Condor P6 Pro) in Android 6.0 Operating System.

I hope you can fix this bug.