Hearts do not show when feeding passive mobs

When feeding passive mobs for breeding (e.g. wheat to cows and sheep), hearts are no longer shown, even if the mob is ready for breeding.

The "use item" animation is shown (the arm holding the wheat shakes), but no hearts are shown.

On feeding two mobs, they still produce an offspring as expected.

Similarly, when feeding baby cows and sheep, no green "plus" particles are shown.