Item dropped when using bone meal on sunflowers, peonies, lilacs or rose bushes appears to be hardcoded

The bug

Using bone meal on several two-block tall flowers will cause them to drop a copy of themselves. This item drop appears to be hardcoded, however, and does not follow any known loot table.

How to reproduce

A data pack that replaces the peony loot table with dirt's is attached to this ticket.

1. Download and apply this data pack

2. Break a peony

3. Use bone meal on a peony

Expected results

Since peonies drop dirt, using bone meal on one would also produce dirt.

Actual results

It does not produce dirt, meaning that the item drop must be hardcoded and not tied to a loot table.

How to fix

Introduce four new loot tables, one for each type of two block tall flower which supports bone meal usage, which is referenced when bone meal is used on them.