When the user attempts to place vines on a block, the vine will not place. This is being seen in both Creative Mode and Survival Mode in a clean world.

This issue was not reproducible in snapshot 15w36d. Vines could be placed in both Creative and Survival mode.

Attached is a screenshot of the F3 for my 15w37a world. I have also attached a quick video of the issue.

Steps to Reproduce:
1.) Launch Minecraft on a PC using the 1.6.39 launcher
2.) Create a profile that uses the most recent snapshot (15w37a)
3.) Create a fresh world using the following setup:
a) Survival mode
b) Cheats and Bonus Chest ON
c) World seed blank
4.) Launch game
5.) Change game mode to /gamemode 1 and give the player a stack of vines
6.) Attempt to place on a tree or other valid block
7.) Observe that the vines do not place on any surface
8.) Repeat steps 6-8, but change the game mode back to /gamemode 0