When placing a structure in a region filled with water blocks that can be waterlogged, will in fact become waterlogged.

Steps to reproduce:

1. Have an region filled with water
2. Place a structure containing waterlog-able blocks, with either a structure block or by command

Result:

1. Structure is placed
2. Waterlog-able blocks become waterlogged

Expected result:

1. Structure is placed
2. All blocks are created as defined in the structure