/setblock air in a waterlogged block places water instead

The bug

When using /setblock (or /fill) to place air in a block, it fails if the block is currently waterlogged, placing water instead. /clone works fine.

How to reproduce

1. Place slab
2. Place water in it
3. Stand on the slab
4. /setblock ~ ~ ~ air
   →  Water is placed

Expected behavior

Block should end up as pure air. Otherwise, this results in the following contradiction:

/setblock ~ ~ ~ air
/testforblock ~ ~ ~ air
Block not found