Rottten Flesh Does Nothing

Please provide a screenshot

Rotten flesh sometimes (20%) not cause hunger in PC version too. I can't see any bug here.

Agree with Mustafa, sometimes rotten flesh doesn´t cause any effects. This is work as intended.

Works As Intended, for the reasons listed above.
I recommend checking the Minecraft Wiki prior to reporting an issue on the bugtracker, as what seems to be a bug to you may actually be intended.