Immortal cake: slices reappearing.

Eaten cake doesn't retain its "eaten" status after exiting a world.

Eating cake lessens the block by 1/6. After placing it on a Brick block, I ate a slice and exited the world ~2 minutes later. Expected result is that the cake would stay that way. Upon reentry of the world (~1 hour later), the cake had reverted to its whole state and has all its slices again.