The bug:

Both types of dry grass do not drop wheat seeds, which is inconsistent with normal grass. I don't know if this is really a bug, but it is rather more of an inconsistency.

Steps to Reproduce:

1. Place down a lot of dry short grass and dry tall grass.
2. Go into survival.
3. Break all the dry grass you have placed. 

Expected Results:

Dry grass of both types drop wheat seeds.

Observed Result:

Dry grass does not drop wheat seeds.