When using an iron ingot on an iron golem, it does not repair it while also consuming the iron ingot in the process.

What I expected to happen was...:
Iron ingot should have been used up, and the damaged iron golem returns back to its undamaged state.

What actually happened was...:
The iron ingot was used up and the iron golem did not get repaired. Another iron ingot was used and it did get repaired.

Steps to Reproduce:
1. Have an iron golem in a village during the night.
2. The iron golem should fight enough mobs to become visually damaged.
3. Use an iron ingot on the iron golem.